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Июльский Linux Patch Wednesday

Июльский Linux Patch Wednesday

July Linux Patch Wednesday. A total of 2,017 vulnerabilities were addressed (539 in the Linux kernel and 504 in Chromium). For comparison, there were 1,888 vulnerabilities in June. Once again, a new record. Moreover, next month will most likely set another record, as 1,704 vulnerabilities have already been addressed 2.5 weeks before the August LPW. 🤷‍♂️ But for now, let's take a closer look at the July report. Only one vulnerability shows signs of exploitation in the wild:

🔻 RCE - Gogs (CVE-2025-8110). Gogs is a self-hosted web service for managing Git repositories, similar in purpose to GitHub or GitLab. An attacker can achieve remote code execution by manipulating the .git/config file through symbolic link bypasses and injecting commands via sshCommand. Multiple public exploits are available on GitHub. The vulnerability has been added to the CISA KEV catalog.

There are also 178 vulnerabilities with public exploits available or indications that they exist, but there are currently no signs of exploitation in the wild. For comparison, last month there were 109 such vulnerabilities. Among them, the following stand out:

🔸 RCE - NGINX (CVE-2026-42533). NGINX is a web server and software for handling network requests, which is often used as a reverse proxy, load balancer, and gateway for web applications. An unauthenticated attacker can exploit this vulnerability for remote code execution by sending crafted HTTP requests.

🔸 RCE - libssh2 (CVE-2026-55200). libssh2 is a C library that implements the SSH-2 protocol and allows applications to establish secure SSH connections, execute commands, and transfer files via SFTP/SCP. A remote attacker can send crafted SSH packets with excessively large packet_length values to corrupt heap memory and achieve remote code execution.

🔸 RCE - Linux Kernel "RefluXFS" (CVE-2026-64600). An attacker with an ordinary local account can exploit the vulnerability to overwrite protected files on disk and gain root privileges on affected systems, including installations running SELinux in Enforcing mode. In practice, the vulnerability allows an attacker to set an empty root password.

🔸 RCE - Gogs (CVE-2025-64111). Due to an insufficient patch for CVE-2024-56731, it is still possible to modify files in the .git directory and achieve remote command execution. Based on the exploit code, authentication is required for exploitation.

🔸 CodeInj - MediaWiki (CVE-2026-58025). MediaWiki is a free and open-source web platform for creating and managing wiki websites, powering Wikipedia and other collaborative content editing projects. An attacker with the importupload or import permission (default: sysop group) can craft a malicious XML import file containing serialized PHP objects in params fields, triggering arbitrary object instantiation and potentially leading to remote code execution through gadget chains.

🔸 RCE - FFmpeg (CVE-2026-8461). FFmpeg is a free and open-source collection of libraries and utilities for processing audio and video data. An out-of-bounds write vulnerability in FFmpeg's libavcodec library, specifically in the MagicYUV decoder, allows denial-of-service and, in some cases, can be exploited for remote code execution.

🔸 RCE - 7-Zip (CVE-2026-14266). 7-Zip is a free and open-source file archiver that allows users to create and extract archives in various formats, including its native 7z format, ZIP, RAR, and others. Crafted XZ-compressed data can trigger an overflow of a heap-based buffer. An attacker can leverage this vulnerability to execute code in the context of the current process.

🔸 MemCor - Linux Kernel (CVE-2026-53359). This is essentially a KVM vulnerability. KVM (Kernel-based Virtual Machine) is a virtualization technology built into the Linux kernel that allows multiple isolated virtual machines to run on a single physical server. A KVM escape vulnerability lets a guest escape to the host in a KVM/x86 environment. It is triggerable on both Intel and AMD.

🗒 Full Vulristics report

May Linux Patch Wednesday

May Linux Patch Wednesday

May Linux Patch Wednesday. A total of 1,638 vulnerabilities (474 in the Linux kernel). For comparison, in April there were 1,035 vulnerabilities (a record!). And this time it turns out to be a record again, more than one and a half times higher! The acceleration is both impressive and alarming. But we will see what happens next. At some point it should stabilize. Although the number of critical vulnerabilities is already so high that reviewing all of them becomes quite problematic. For 7 vulnerabilities there are signs of exploitation in the wild. And for another 264 there are public exploits. Let’s start, as usual, with vulnerabilities being actively exploited according to CISA KEV and VulnCheck KEV data. Here, at the top, as expected, are two high-profile ways to get a root shell:

🔻 EoP - Linux Kernel "Copy Fail" (CVE-2026-31431)
🔻 EoP - Linux Kernel "Dirty Frag" (CVE-2026-43500)

Other vulnerabilities being exploited in the wild:

🔻 RCE - Apache ActiveMQ (CVE-2026-40466). Based on the description, this appears to be a bypass of the fix for CVE-2026-34197, which I already wrote about earlier.

🔻 AuthBypass - Rclone (CVE-2026-41176). Rclone ("rsync for cloud storage") is a command-line utility for synchronizing files and directories between various cloud storage services and local systems. Exploitation of the vulnerability can lead to unauthorized access to sensitive administrative functionality, including configuration and operational RC methods.

🔻 RCE - NGINX (CVE-2026-42945). The bug enables unauthenticated remote code execution against servers using rewrite and set directives.

🔻 DoS - PgBouncer (CVE-2026-6664). PgBouncer is a lightweight, open-source connection pooler for PostgreSQL databases. It reduces connection overhead by managing a pool of connections to one or more PostgreSQL servers, improving performance and resource efficiency for applications with frequent short-lived database connections. An integer overflow in the network packet parsing code in PgBouncer before 1.25.2 bypasses a boundary check and can lead to a crash.

🔻 XSS - Postorius (CVE-2026-44742). The Postorius Django app provides a web user interface to access GNU Mailman. Mailman is free software for managing electronic mail discussion and e-newsletter lists. The vulnerability is being exploited according to VulnCheck KEV; however, no public exploits has been observed yet.

From the remaining vulnerabilities with public exploits, but without any signs of exploitation in the wild so far, the following can be highlighted:

🔸 RCE - Apache HTTP Server (CVE-2026-23918). Double-free error in Apache httpd mod_http2 stream cleanup, leading to pre-auth RCE.

🔸 RCE - Apache Tomcat (CVE-2026-34486). Apache Tomcat Tribes cluster communication module fails to discard messages when EncryptInterceptor decryption fails, allowing unauthenticated attackers to trigger Remote Code Execution via Java deserialization on port 4000.

🔸 RCE - ProFTPD (CVE-2026-42167). The flaw exists in how mod_sql handles certain logging variables (like %U), allowing an unauthenticated attacker to inject SQL commands via the USER command.

🔸 EoP - Linux Kernel "DirtyDecrypt" (CVE-2026-31635). Linux local privilege escalation in the RxRPC/GSSAPI decryption path. A missing skb_cow_data() check in rxgk_decrypt_skb() allows an unprivileged local attacker to corrupt cache pages and overwrite in-memory contents of read-only files.

🔸 EoP - Linux Kernel "Fragnesia" (CVE-2026-46300). I also analyzed this vulnerability earlier. A bug in skb_try_coalesce() allowing page-cache write via fragmented ESP packets.

🔸 EoP - Linux Kernel (CVE-2026-46333). Local root privilege escalation and credential disclosure in the Linux kernel ptrace path, discovered by researchers at Qualys.

🔸 EoP - PackageKit "Pack2TheRoot" (CVE-2026-41651). PackageKit is a free and open-source suite of software applications designed to provide a consistent and high-level abstraction layer for a number of different package management systems. The vulnerability allows an attacker to escalate privileges, potentially gaining root access or compromising the system.

🔸 ComInj - Composer (CVE-2026-40261, CVE-2026-40176). Composer is a dependency manager for PHP. The vulnerability exists in the Perforce::generateP4Command() method. Due to insufficient sanitization of repository configuration parameters (such as url, p4user, or client) when constructing shell commands, an attacker who controls a composer.json file can execute arbitrary commands on the victim's system when composer install or composer update is executed.

🗒 Full Vulristics report

Making simple Nmap SPA web GUI with Apache, AngularJS and Python Twisted

Making simple Nmap SPA web GUI with Apache, AngularJS and Python Twisted. The last time I was developing dynamic web applications years ago. I used CGI and PHP back then. 🙂 Now I am really interested in a modern approach, when you have a Single Page Web Application (SPA) written in HTML and JavaScript, that makes http requests to some external API.

It’s pretty cool, because your application becomes API-centric naturally. You work on human interface and improve integration capabilities at the same time. And the task of securing your web app mostly reduces to securing your formalized API.

nmap SPA GUI

The very best way to learn something new is to write a post about this stuff. 😉 Here I will reproduce my own steps of making a very basic web app:

  1. Launch Apache web-server with http/https.
  2. Make a simple API service: Nmap wrapper.
  3. Make a web-application with “multipage” experience. There should be at least two pages: Scan and About.
  4. On Scan page it will be possible to input a target (hostname or IP), scan arguments and  launch scan by clicking on the button. The same behavior will be if the target will be passed as a parameter in address bar.
  5. On other pages should be some static text.

As you can see, it is a very limited task, but it should clear up the most confusing parts of the process.

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Vulners - Google for hacker. How the best vulnerability search engine works and how to use it

Vulners – Google for hacker. How the best vulnerability search engine works and how to use it. Original article was published in Xakep Magazine #06/2016 (in Russian)

vulners.com logo

The common task. Уou need to find all information about some vulnerability: how critical the bug is, whether there is a public exploit, which vendors already released patches, which vulnerability scanner can detect this bug in the system. Previously, you had to search it all manually in dozens of sources (CVEDetails, SecurityFocus, Rapid7 DB, Exploit-DB, CVEs from MITRE / NIST, vendor newsletters, etc.) and analyze the collected data. Today, this routine can be (and should be!) automated with specialized services. One of these services – Vulners.com, the coolest search engine for bugs. And what is the most important – it’s free and has an open API. Let’s see how it can be useful for us.

What is it?

Vulners is a very large constantly updating database of Information Security content. This site lets you search for vulnerabilities, exploits, patches, bug bounty programs the same way a web search engine lets you search for websites. Vulners aggregates and presents in convenient form seven major types of data:

  • Popular vulnerability databases, containing general descriptions of vulnerabilities and links. For example, well-known NVD CVEs of MITRE US agency and NIST Institute. In addition to this, Vulners supports vulnerability descriptions from various research centers and response teams: Vulnerability Lab, XSSed, CERT, ICS, Zero Day Initiative, Positive Technologies, ERPScan.
  • Vendor’s security bulletins. This bug-reports are published by software vendors and contain information about vulnerabilities in their own products. At current moment Vulners supports various Linux distributions (Red Hat, CentOS, Oracle Linux, Arch Linux, Debian, Ubuntu, SUSE), FreeBSD, network devices (F5 Networks, Cisco, Huawei, Palo Alto Networks), popular and critical software (OpenSSL, Samba, nginx, Mozilla, Opera), including CMS (WordPress, Drupal).
  • Exploits from Exploit-DB, Metasploit and 0day.today. Exploits are parsed and stored in full-text form and you can read the sources in a convenient text editor.
  • Nessus plugins for vulnerability detection. It makes easy to find out whether a particular vulnerability can be detected using this popular network scanner. Why is it important? Read in my article “When a free scanning service detects vulnerabilities better“.
  • Bug disclousers for bug bounty programs. At current moment Vulners supports HackerOne and Open Bug Bounty.
  • Potential vulnerabilities of mobile applications and CMS. It is possible in cooperation with the static application security testing (SAST) vendors Hackapp and InfoWatch APPERCUT.
  • Posts from hacking resources. Vulners collects Threatpost and rdot.org publications, which often cover vulnerability related topics.

All this information is handled, cataloged, structured and is always available for the search.

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