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USN-8741-1: Flatpak vulnerabilities

Ubuntu patched two Flatpak flaws, including a sandbox escape via app-controlled symlinks allowing host code execution (CVE-2026-34078).

Ubuntu security notice USN-8741-1 fixes two Flatpak vulnerabilities in Ubuntu 20.04 LTS, 22.04 LTS, and 24.04 LTS. CVE-2026-34078 stems from improper path validation in sandbox-expose options, letting a malicious or compromised Flatpak app use app-controlled symlinks to access arbitrary host files and gain code execution in the host context. CVE-2026-34079 involves improper path validation when removing outdated ld.so cache files, allowing a compromised app to delete arbitrary files on the host.

2026-005: High Vulnerability in the Linux Kernel ("Copy Fail")

Linux kernel flaw CVE-2026-31431 ('Copy Fail', CVSS 7.8) allows unprivileged users to gain root via AF_ALG; a public PoC is out and most distros remain unpatched.

Disclosed on 29 April 2026, CVE-2026-31431 is a local privilege escalation in the Linux kernel's algif_aead module (AF_ALG crypto API), CVSS 7.8, stemming from a 2017 in-place optimisation. By chaining an AF_ALG socket operation with splice(), an unprivileged user can write 4 bytes into an arbitrary page-cache page, e.g. corrupting a setuid binary like /usr/bin/su to obtain a root shell. It affects virtually all kernels built since 2017, including Ubuntu 20.04-24.04, Amazon Linux 2023, RHEL 10.1, and SUSE 16; the mainline fix landed 1 April 2026 but no vendor packages were available as of 30 April. CERT-EU recommends the interim mitigation (disable algif_aead) and blocking AF_ALG via seccomp, prioritising Kubernetes nodes and CI/CD runners.

CERT-EU Advisoriesupdated · 9d agofirst · Apr 29, 2026Exploit / PoC 6 sourcesCVE-2026-31431

USN-8763-1: kitty vulnerabilities

Ubuntu patches three kitty terminal flaws including remote command execution via crafted escape sequences.

Ubuntu Security Notice USN-8763-1 fixes multiple vulnerabilities in the kitty terminal emulator. CVE-2026-42850 allows a remote attacker to execute arbitrary commands via improperly escaped error messages triggered by crafted terminal escape sequences. CVE-2026-42851 enables arbitrary code execution with the user's privileges through mishandled remote edit requests in terminal output. CVE-2026-54055 lets a local attacker overwrite arbitrary files via destination paths in kitty's file transmission protocol.

New ZcopyReaper Linux Kernel Vulnerability Enables Privilege Escalation Attacks

ZcopyReaper (CVE-2026-43502) lets unprivileged local attackers reach root on Linux via an RDS zero-copy cleanup flaw dating to kernel 4.17.

CVE-2026-43502 is a lifetime-management error in rds_message_purge() that mishandles zero-copy sends before socket attachment, corrupting kernel memory and enabling local privilege escalation without capabilities or user namespaces. NebuSec demonstrated the exploit on openSUSE kernel 6.4.0-150600.23.100; vulnerable systems need CONFIG_INET, CONFIG_AIO, CONFIG_RDS, and CONFIG_RDS_TCP. The fix landed in mainline commit 44b550d88b26 (Linux 7.1-rc3) with backports to Ubuntu 7.0.0, 6.8.0, and 5.15.0 kernels and multiple Debian branches. NebuSec also released public exploits for 20 additional Linux kernel vulnerabilities in its CyberMeowfia repository.

USN-8753-1: libinput vulnerability

Ubuntu patches libinput flaw letting local attackers inject udev properties and execute arbitrary code as root.

USN-8753-1 fixes a libinput vulnerability where device properties are not properly escaped. A local attacker could inject arbitrary udev properties and execute arbitrary code as root, a full local privilege escalation on affected Linux desktop systems. Ubuntu shipped updated packages.

Ubuntu Security Notices · 1d agoAdvisory

PostgreSQL Fixes 12-Year-Old Logical Decoding Flaw Enabling Replication-Role Code Execution

PostgreSQL fixed CVE-2026-6471 (CVSS 7.2), a 12-year-old logical decoding flaw letting replication-role accounts execute arbitrary code as the database OS user.

PostgreSQL patched CVE-2026-6471 (CVSS 7.2), a flaw present since logical decoding shipped in 9.4 (2014) that lets an account with the REPLICATION attribute run arbitrary code as the database server's OS user when wal_level is logical. Versions before 18.6, 17.11, 16.15, 15.19, and 14.24 are affected; exploitation requires such an account, which backup, CDC, and monitoring tooling routinely holds. The fix adds an output_plugin_libraries whitelist, so administrators using non-default plugins such as wal2json and decoderbufs must add them and reload configuration after updating. Cyera Research, whose write-up names the flaw PostGREShell, demonstrated escalating a replication user to superuser with persistence; no PoC or KEV entry existed as of September 4.

The Hacker News · 11d agoVulnerabilityCVE-2026-64711