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cPanel, WHM Release Fixes for Three New Vulnerabilities — Patch Now

The Hacker News - 2 hodiny 6 min zpět
cPanel has released updates to address three vulnerabilities in cPanel and Web Host Manager (WHM) that could be exploited to achieve privilege escalation, code execution, and denial-of-service. The list of vulnerabilities is as follows - CVE-2026-29201 (CVSS score: 4.3) - An insufficient input validation of the feature file name in the "feature::LOADFEATUREFILE" adminbin call that could result Ravie Lakshmananhttp://www.blogger.com/profile/[email protected]
Kategorie: Hacking & Security

Chaos erupts as cyberattack disrupts learning platform Canvas amid finals

Ars Technica - 8 Květen, 2026 - 20:33

Chaos erupted at schools and colleges throughout the US on Thursday as a cyberattack disrupted online learning platform Canvas just as students were due to take final exams.

Canvas parent company Instructure said that as of Friday morning, the platform was back online. Instructure said it temporarily took Canvas offline on Thursday after identifying unauthorized activity in its network. The threat actor was the same one responsible for a data breach that Instructure disclosed a week ago. Data accessed included user names, email addresses, student ID numbers, and messages exchanged on the platform. The company said it has no indication that passwords, dates of birth, government identifiers, or financial information were involved.

Schools and colleges scramble

A ransomware group known as ShinyHunters claimed responsibility for the breach on its dark web site. It claimed the data it took came from 275 million people associated with 8,800 schools.

Read full article

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TCLBANKER Banking Trojan Targets Financial Platforms via WhatsApp and Outlook Worms

The Hacker News - 8 Květen, 2026 - 20:12
Threat hunters have flagged a previously undocumented Brazilian banking trojan dubbed TCLBANKER that's capable of targeting 59 banking, fintech, and cryptocurrency platforms. The activity is being tracked by Elastic Security Labs under the moniker REF3076. The malware family is assessed to be a major update of the Maverick, which is known to leverage a worm called SORVEPOTEL to spread via Ravie Lakshmananhttp://www.blogger.com/profile/[email protected]
Kategorie: Hacking & Security

NVIDIA confirms GeForce NOW data breach affecting Armenian users

Bleeping Computer - 8 Květen, 2026 - 18:18
NVIDIA has confirmed in a statement for BleepingComputer that GeForce NOW user information has been exposed in a data breach. [...]
Kategorie: Hacking & Security

Fake Call History Apps Stole Payments From Users After 7.3 Million Play Store Downloads

The Hacker News - 8 Květen, 2026 - 17:08
Cybersecurity researchers have discovered fraudulent apps on the official Google Play Store for Android that falsely claimed to offer access to call histories for any phone number, only to trick users into joining a subscription that provided fake data and incurred financial loss. The 28 apps have collectively racked up more than 7.3 million downloads, with one of them alone accounting for over Ravie Lakshmananhttp://www.blogger.com/profile/[email protected]
Kategorie: Hacking & Security

Linux Attackers Abuse Admin Tools For Stealthy Intrusions

LinuxSecurity.com - 8 Květen, 2026 - 16:06
A lot of Linux attacks now look like normal admin activity. Attackers use SSH , cron , curl , systemd , cloud scripts, and other trusted tools that defenders already expect to see running across production systems.
Kategorie: Hacking & Security

Why More Analysts Won’t Solve Your SOC’s Alert Problem

Bleeping Computer - 8 Květen, 2026 - 16:02
Attackers move faster than overwhelmed SOC teams can realistically investigate alerts. Prophet Security breaks down how AI can help analysts investigate alerts faster and focus on real threats. [...]
Kategorie: Hacking & Security

One Click, Total Shutdown: The "Patient Zero" Webinar on Killing Stealth Breaches

The Hacker News - 8 Květen, 2026 - 16:01
The hardest part of cybersecurity isn't the technology, it’s the people. Every major breach you’ve read about lately usually starts the same way: one employee, one clever email, and one "Patient Zero" infection. In 2026, hackers are using AI to make these "first clicks" nearly impossible to spot. If a single laptop gets compromised on your watch, do you have a plan to stop it from taking down [email protected]
Kategorie: Hacking & Security

Ubuntu Dirty Frag Important Local Privilege Escalation Exploit

LinuxSecurity.com - 8 Květen, 2026 - 15:30
Just weeks after Linux defenders began responding to Copy Fail , researchers have disclosed another serious privilege escalation vulnerability that can deliver reliable root access on major distributions.
Kategorie: Hacking & Security

Apple vs. social engineering: Terminal paste trap blocked

Computerworld.com [Hacking News] - 8 Květen, 2026 - 15:25

Echoing concerns from other security experts, Orange Cyberdefense (OC) recently warned that employees have become the biggest security threat faced by business. 

Now, in the latest illustration of its ongoing security response, Apple is putting new protections in place in macOS 26.4 that should help – but employee education remains critical as hackers turn to complex, multi-stage, social engineering attacks to infest systems with malware.

Your people are your weakness

The data tells its own story. OC explains: Employees account for 57% of all security incidents and 45% of these incidents come when workers bypass or ignore security policies by, for example, using unapproved tools. 

Attackers are actively searching for and exploiting those kinds of policy workarounds, seeking weaknesses in commonly used, but unapproved, tools. Users really should educate themselves.

While companies can put some mitigations in place using device management and policy controls to constrain app use and downloads across their endpoints, Apple is also working to keep systems secure with a focus on the Terminal app. 

Terminal’s early warning system

In this case, it will introduce new malware warnings and protections to help prevent people from using Terminal to override system security to install malware-laden scripts. That’s the attack vector currently being used in the ClickFix series of attacks, which use fake macOS utilities to trick Mac users into doing just that.

It’s yet another example of how attackers rely on complex social engineering attacks to fool targets into undermining their own security. These attacks often begin with an attempt to get users to install infostealer malware on their own machines, and run them, bypassing Mac’s native malware defence.

Apple already has many, many protections to help combat attacks like these; now, we’ll see warnings in macOS Tahoe 26.4 whenever a relatively novice user pastes anything into the Terminal. Apple’s XProtect continues to block known malicious scripts. 

Helping people make better decisions

These warnings don’t appear in the first 24 hours after setting up a Mac, nor do they appear if a user has developer tools such as Xcode installed. That’s because Apple assumes developers are savvy enough to avoid falling for such tricks, while many users setting up their Macs may have legitimate need to use Terminal for legitimate purposes. (Apple will always warn when you try to paste code from sources known to be malicious.)

To an extent, Apple’s new protection reflects its belief that users should have choice while ensuring they are informed. Figuring out when to warn a user of the dangers they take has always been a challenge, as you don’t want to interfere in the user experience too heavily. But the prevalence of the kinds of threats OC warns about pushed Apple to put a new gate in place. 

FileVault keys come to the Passwords app

This isn’t the only new protection Apple has planned for macOS 26.4. The update does something many have long wanted. Ever since Apple’s first M-series chips arrived, we’ve had situations in which users forget their FileVault key, which can lead to Macs getting bricked when sold. Apple has now moved the macOS FileVault recovery key into users’ end-to-end encrypted Passwords app.

That’s good in two ways: it removes the threat Apple could lose or leak the key and makes it easier for a user to recover that key using the Passwords app on anther device. When you protect the data on your Mac with FileVault, you get a recovery key during set-up. If you forget the password for your Mac, you can reset the password by entering the recovery key.

Finally, IT admins seeking to ensure compliance with security policies will appreciate that Apple began rolling out Background Security Improvements in iOS 26.3.1, iPadOS 26.3.1 and macOS 26.3.1 to deliver incremental fixes and additional protections in between normal software updates. Still, as the OC data shows, the best and most effective security (beyond moving to a Mac) is to ensure employees fully understand the implications and significance of your company’s current security policies.

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Kategorie: Hacking & Security

Trellix source code breach claimed by RansomHouse hackers

Bleeping Computer - 8 Květen, 2026 - 15:23
The attack on the Trellix source code repository disclosed last week has been claimed by the RansomHouse threat group, which leaked a small set of images as proof of the intrusion. [...]
Kategorie: Hacking & Security

CISA gives feds four days to patch Ivanti flaw exploited as zero-day

Bleeping Computer - 8 Květen, 2026 - 14:16
CISA has given U.S. federal agencies four days to secure their networks against a high-severity vulnerability in Ivanti Endpoint Manager Mobile (EPMM) exploited in zero-day attacks. [...]
Kategorie: Hacking & Security

Quasar Linux RAT Steals Developer Credentials for Software Supply Chain Compromise

The Hacker News - 8 Květen, 2026 - 13:00
A previously undocumented Linux implant codenamed Quasar Linux RAT (QLNX) is targeting developers' systems to establish a silent foothold as well as facilitate a broad range of post-compromise functionality, such as credential harvesting, keylogging, file manipulation, clipboard monitoring, and network tunneling. "QLNX targets developers and DevOps credentials across the software supply chain," Ravie Lakshmananhttp://www.blogger.com/profile/[email protected]
Kategorie: Hacking & Security

Zara data breach exposed personal information of 197,000 people

Bleeping Computer - 8 Květen, 2026 - 12:42
Hackers who gained access to the databases of Spanish fast-fashion retailer Zara stole data belonging to more than 197,000 customers, according to data breach notification service Have I Been Pwned. [...]
Kategorie: Hacking & Security

One Missed Threat Per Week: What 25M Alerts Reveal About Low-Severity Risk

The Hacker News - 8 Květen, 2026 - 12:30
The dark secret of enterprise security operations is that defenders have quietly institutionalized the practice of not looking. This is not just anecdotal, but rather backed by a recent report investigating more than 25 million security alerts, including informational and low-severity, across live enterprise environments.  The dataset behind these findings includes 10 million monitored [email protected]
Kategorie: Hacking & Security

Former govt contractor convicted for wiping dozens of federal databases

Bleeping Computer - 8 Květen, 2026 - 10:45
A 34-year-old Virginia man was found guilty of conspiring to destroy dozens of government databases after getting fired from his job as a federal contractor. [...]
Kategorie: Hacking & Security

New Linux PamDOORa Backdoor Uses PAM Modules to Steal SSH Credentials

The Hacker News - 8 Květen, 2026 - 10:41
Cybersecurity researchers have disclosed details of a new Linux backdoor named PamDOORa that's being advertised on the Rehub Russian cybercrime forum for $1,600 by a threat actor called "darkworm." The backdoor is designed as a Pluggable Authentication Module (PAM)-based post-exploitation toolkit that enables persistent SSH access by means of a magic password and specific TCP port combination. Ravie Lakshmananhttp://www.blogger.com/profile/[email protected]
Kategorie: Hacking & Security

Linux Firewall Rules Management Challenges Kubernetes Security

LinuxSecurity.com - 8 Květen, 2026 - 10:21
A Linux server running a few predictable services is relatively easy to secure.
Kategorie: Hacking & Security

CVE-2025-68670: discovering an RCE vulnerability in xrdp

Kaspersky Securelist - 8 Květen, 2026 - 10:00

In addition to KasperskyOS-powered solutions, Kaspersky offers various utility software to streamline business operations. For instance, users of Kaspersky Thin Client, an operating system for thin clients, can also purchase Kaspersky USB Redirector, a module that expands the capabilities of the xrdp remote desktop server for Linux. This module enables access to local USB devices, such as flash drives, tokens, smart cards, and printers, within a remote desktop session – all while maintaining connection security.

We take the security of our products seriously and regularly conduct security assessments. Kaspersky USB Redirector is no exception. Last year, during a security audit of this tool, we discovered a remote code execution vulnerability in the xrdp server, which was assigned the identifier CVE-2025-68670. We reported our findings to the project maintainers, who responded quickly: they fixed the vulnerability in version 0.10.5, backported the patch to versions 0.9.27 and 0.10.4.1, and issued a security bulletin. This post breaks down the details of CVE-2025-68670 and provides recommendations for staying protected.

Client data transmission via RDP

Establishing an RDP connection is a complex, multi-stage process where the client and server exchange various settings. In the context of the vulnerability we discovered, we are specifically interested in the Secure Settings Exchange, which occurs immediately before client authentication. At this stage, the client sends protected credentials to the server within a Client Info PDU (protocol data unit with client info): username, password, auto-reconnect cookies, and so on. These data points are bundled into a TS_INFO_PACKET structure and can be represented as Unicode strings up to 512 bytes long, the last of which must be a null terminator. In the xrdp code, this corresponds to the xrdp_client_info structure, which looks as follows:

{ [..SNIP..] char username[INFO_CLIENT_MAX_CB_LEN]; char password[INFO_CLIENT_MAX_CB_LEN]; char domain[INFO_CLIENT_MAX_CB_LEN]; char program[INFO_CLIENT_MAX_CB_LEN]; char directory[INFO_CLIENT_MAX_CB_LEN]; [..SNIP..] }

The value of the INFO_CLIENT_MAX_CB_LEN constant corresponds to the maximum string length and is defined as follows:

#define INFO_CLIENT_MAX_CB_LEN 512

When transmitting Unicode data, the client uses the UTF-16 encoding. However, the server converts the data to UTF-8 before saving it.

if (ts_info_utf16_in( // [1] s, len_domain, self->rdp_layer->client_info.domain, sizeof(self->rdp_layer->client_info.domain)) != 0) // [2] { [..SNIP..] }

The size of the buffer for unpacking the domain name in UTF-8 [2] is passed to the ts_info_utf16_in function [1], which implements buffer overflow protection [3].

static int ts_info_utf16_in(struct stream *s, int src_bytes, char *dst, int dst_len) { int rv = 0; LOG_DEVEL(LOG_LEVEL_TRACE, "ts_info_utf16_in: uni_len %d, dst_len %d", src_bytes, dst_len); if (!s_check_rem_and_log(s, src_bytes + 2, "ts_info_utf16_in")) { rv = 1; } else { int term; int num_chars = in_utf16_le_fixed_as_utf8(s, src_bytes / 2, dst, dst_len); if (num_chars > dst_len) // [3] { LOG(LOG_LEVEL_ERROR, "ts_info_utf16_in: output buffer overflow"); rv = 1; } / / String should be null-terminated. We haven't read the terminator yet in_uint16_le(s, term); if (term != 0) { LOG(LOG_LEVEL_ERROR, "ts_info_utf16_in: bad terminator. Expected 0, got %d", term); rv = 1; } } return rv; }

Next, the in_utf16_le_fixed_as_utf8_proc function, where the actual data conversion from UTF-16 to UTF-8 takes place, checks the number of bytes written [4] as well as whether the string is null-terminated [5].

{ unsigned int rv = 0; char32_t c32; char u8str[MAXLEN_UTF8_CHAR]; unsigned int u8len; char *saved_s_end = s->end; // Expansion of S_CHECK_REM(s, n*2) using passed-in file and line #ifdef USE_DEVEL_STREAMCHECK parser_stream_overflow_check(s, n * 2, 0, file, line); #endif // Temporarily set the stream end pointer to allow us to use // s_check_rem() when reading in UTF-16 words if (s->end - s->p > (int)(n * 2)) { s->end = s->p + (int)(n * 2); } while (s_check_rem(s, 2)) { c32 = get_c32_from_stream(s); u8len = utf_char32_to_utf8(c32, u8str); if (u8len + 1 <= vn) // [4] { /* Room for this character and a terminator. Add the character */ unsigned int i; for (i = 0 ; i < u8len ; ++i) { v[i] = u8str[i]; } v n -= u8len; v += u8len; } else if (vn > 1) { /* We've skipped a character, but there's more than one byte * remaining in the output buffer. Mark the output buffer as * full so we don't get a smaller character being squeezed into * the remaining space */ vn = 1; } r v += u8len; } // Restore stream to full length s->end = saved_s_end; if (vn > 0) { *v = '\0'; // [5] } + +rv; return rv; }

Consequently, up to 512 bytes of input data in UTF-16 are converted into UTF-8 data, which can also reach a size of up to 512 bytes.

CVE-2025-68670: an RCE vulnerability in xrdp

The vulnerability exists within the xrdp_wm_parse_domain_information function, which processes the domain name saved on the server in UTF-8. Like the functions described above, this one is called before client authentication, meaning exploitation does not require valid credentials. The call stack below illustrates this.

x rdp_wm_parse_domain_information(char *originalDomainInfo, int comboMax, int decode, char *resultBuffer) xrdp_login_wnd_create(struct xrdp_wm *self) xrdp_wm_init(struct xrdp_wm *self) xrdp_wm_login_state_changed(struct xrdp_wm *self) xrdp_wm_check_wait_objs(struct xrdp_wm *self) xrdp_process_main_loop(struct xrdp_process *self)

The code snippet where the vulnerable function is called looks like this:

char resultIP[256]; // [7] [..SNIP..] combo->item_index = xrdp_wm_parse_domain_information( self->session->client_info->domain, // [6] combo->data_list->count, 1, resultIP /* just a dummy place holder, we ignore */ );

As you can see, the first argument of the function in line [6] is the domain name up to 512 bytes long. The final argument is the resultIP buffer of 256 bytes (as seen in line [7]). Now, let’s look at exactly what the vulnerable function does with these arguments.

static int xrdp_wm_parse_domain_information(char *originalDomainInfo, int comboMax, int decode, char *resultBuffer) { int ret; int pos; int comboxindex; char index[2]; /* If the first char in the domain name is '_' we use the domain name as IP*/ ret = 0; /* default return value */ /* resultBuffer assumed to be 256 chars */ g_memset(resultBuffer, 0, 256); if (originalDomainInfo[0] == '_') // [8] { /* we try to locate a number indicating what combobox index the user * prefer the information is loaded from domain field, from the client * We must use valid chars in the domain name. * Underscore is a valid name in the domain. * Invalid chars are ignored in microsoft client therefore we use '_' * again. this sec '__' contains the split for index.*/ pos = g_pos(&originalDomainInfo[1], "__"); // [9] if (pos > 0) { /* an index is found we try to use it */ LOG(LOG_LEVEL_DEBUG, "domain contains index char __"); if (decode) { [..SNIP..] } / * pos limit the String to only contain the IP */ g_strncpy(resultBuffer, &originalDomainInfo[1], pos); // [10] } else { LOG(LOG_LEVEL_DEBUG, "domain does not contain _"); g_strncpy(resultBuffer, &originalDomainInfo[1], 255); } } return ret; }

As seen in the code, if the first character of the domain name is an underscore (line [8]), a portion of the domain name – starting from the second character and ending with the double underscore (“__”) – is written into the resultIP buffer (line [9]). Since the domain name can be up to 512 bytes long, it may not fit into the buffer even if it’s technically well-formed (line [10]). Consequently, the overflow data will be written to the thread stack, potentially modifying the return address. If an attacker crafts a domain name that overflows the stack buffer and replaces the return address with a value they control, execution flow will shift according to the attacker’s intent upon returning from the vulnerable function, allowing for arbitrary code execution within the context of the compromised process (in this case, the xrdp server).

To exploit this vulnerability, the attacker simply needs to specify a domain name that, after being converted to UTF-8, contains more than 256 bytes between the initial “_” and the subsequent “__”. Given that the conversion follows specific rules easily found online, this is a straightforward task: one can simply take advantage of the fact that the length of the same string can vary between UTF-16 and UTF-8. In short, this involves avoiding ASCII and certain other characters that may take up more space in UTF-16 than in UTF-8, while also being careful not to abuse characters that expand significantly after conversion. If the resulting UTF-8 domain name exceeds the 512-byte limit, a conversion error will occur.

PoC

As a PoC for the discovered vulnerability, we created the following RDP file containing the RDP server’s IP address and a long domain name designed to trigger a buffer overflow. In the domain name, we used a specific number of K (U+041A) characters to overwrite the return address with the string “AAAAAAAA”. The contents of the RDP file are shown below:

alternate full address:s:172.22.118.7 full address:s:172.22.118.7 domain:s:_veryveryveryverKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKeryveryveryveryveryveryveryveryveryveryveryveryveryveryveryveryveryveryveryveaaaaaaaaryveryveryveryveryveryveryveryveryveryveryveryverylongdoAAAAAAAA__0 username:s:testuser

When you open this file, the mstsc.exe process connects to the specified server. The server processes the data in the file and attempts to write the domain name into the buffer, which results in a buffer overflow and the overwriting of the return address. If you look at the xrdp memory dump at the time of the crash, you can see that both the buffer and the return address have been overwritten. The application terminates during the stack canary check. The example below was captured using the gdb debugger.

gef➤ bt #0 __pthread_kill_implementation (no_tid=0x0, signo=0x6, threadid=0x7adb2dc71740) at ./nptl/pthread_kill.c:44 #1 __pthread_kill_internal (signo=0x6, threadid=0x7adb2dc71740) at ./nptl/pthread_kill.c:78 #2 __GI___pthread_kill (threadid=0x7adb2dc71740, signo=signo@entry=0x6) at./nptl/pthread_kill.c:89 #3 0x00007adb2da42476 in __GI_raise (sig=sig@entry=0x6) at ../sysdeps/posix/raise.c:26 #4 0x00007adb2da287f3 in __GI_abort () at ./stdlib/abort.c:79 #5 0x00007adb2da89677 in __libc_message (action=action@entry=do_abort, fmt=fmt@entry=0x7adb2dbdb92e "*** %s ***: terminated\n") at ../sysdeps/posix/libc_fatal.c:156 #6 0x00007adb2db3660a in __GI___fortify_fail (msg=msg@entry=0x7adb2dbdb916 "stack smashing detected") at ./debug/fortify_fail.c:26 #7 0x00007adb2db365d6 in __stack_chk_fail () at ./debug/stack_chk_fail.c:24 #8 0x000063654a2e5ad5 in ?? () #9 0x4141414141414141 in ?? () #10 0x00007adb00000a00 in ?? () #11 0x0000000000050004 in ?? () #12 0x00007fff91732220 in ?? () #13 0x000000000000030a in ?? () #14 0xfffffffffffffff8 in ?? () #15 0x000000052dc71740 in ?? () #16 0x3030305f70647278 in ?? () #17 0x616d5f6130333030 in ?? () #18 0x00636e79735f6e69 in ?? () #19 0x0000000000000000 in ?? ()

Protection against vulnerability exploitation

It is worth noting that the vulnerable function can be protected by a stack canary via compiler settings. In most compilers, this option is enabled by default, which prevents an attacker from simply overwriting the return address and executing a ROP chain. To successfully exploit the vulnerability, the attacker would first need to obtain the canary value.

The vulnerable function is also referenced by the xrdp_wm_show_edits function; however, even in that case, if the code is compiled with secure settings (using stack canaries), the most trivial exploitation scenario remains unfeasible.

Nevertheless, a stack canary is not a panacea. An attacker could potentially leak or guess its value, allowing them to overwrite the buffer and the return address while leaving the canary itself unchanged. In the security bulletin dedicated to CVE-2025-68670, the xrdp maintainers advise against relying solely on stack canaries when using the project.

Vulnerability remediation timeline
  • 12/05/2025: we submitted the vulnerability report via https://github.com/neutrinolabs/xrdp/security.
  • 12/05/2025: the project maintainers immediately confirmed receipt of the report and stated they would review it shortly.
  • 12/15/2025: investigation and prioritization of the vulnerability began.
  • 12/18/2025: the maintainers confirmed the vulnerability and began developing a patch.
  • 12/24/2025: the vulnerability was assigned the identifier CVE-2025-68670.
  • 01/27/2026: the patch was merged into the project’s main branch.
Conclusion

Taking a responsible approach to code makes not only our own products more solid but also enhances popular open-source projects. We have previously shared how security assessments of KasperskyOS-based solutions – such as Kaspersky Thin Client and Kaspersky IoT Secure Gateway – led to the discovery of several vulnerabilities in Suricata and FreeRDP, which project maintainers quickly patched. CVE-2025-68670 is yet another one of those stories.

However, discovering a vulnerability is only half the battle. We would like to thank the xrdp maintainers for their rapid response to our report, for fixing the vulnerability, and for issuing a security bulletin detailing the issue and risk mitigation options.

New Linux 'Dirty Frag' zero-day gives root on all major distros

Bleeping Computer - 8 Květen, 2026 - 09:45
A new Linux zero-day exploit, named Dirty Frag, allows local attackers to gain root privileges on most major Linux distributions with a single command. [...]
Kategorie: Hacking & Security
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