ESB-2026.6692

=========================================================================== AUSCERT External Security Bulletin Redistribution ESB-2026.6692 USN-8349-3: rsync regression 17 June 2026 =========================================================================== AUSCERT Security Bulletin Summary --------------------------------- Product: rsync Publisher: Ubuntu Operating System: Ubuntu Resolution: Patch/Upgrade CVE Names: CVE-2026-43619 CVE-2026-43620 CVE-2026-45232 CVE-2025-10158 CVE-2026-41035 CVE-2026-29518 CVE-2026-43617 CVE-2026-43618 Original Bulletin: https://ubuntu.com/security/notices/USN-8349-3 Comment: CVSS (Max): 8.1 CVE-2026-43618 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H) CVSS Source: [VulnCheck], NIST, Rapid7 Calculator: https://www.first.org/cvss/calculator/3.1#CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H EPSS (Max): 0.6% (45th) CVE-2026-43618 2026-06-16 - --------------------------BEGIN INCLUDED TEXT-------------------- USN-8349-3: rsync regression Publication date 16 June 2026 Overview USN-8349-1 introduced regressions in rsync. Releases 20.04 LTS 18.04 LTS 16.04 LTS 14.04 LTS --------------------------------------------------------------------------------- Open side navigation Packages o rsync - fast, versatile, remote (and local) file-copying tool Details USN-8349-1 fixed vulnerabilities in rsync. Unfortunately that update introduced multiple regressions in rsync functionality. This update fixes the problem. We apologize for the inconvenience. Original advisory details: Calum Hutton discovered that rsync contained a heap-based out-of-bounds read when handling file transfers. A remote attacker with read access to an rsync server could possibly use this issue to cause a denial of service. ( CVE-2025-10158 ) Batuhan Sancak, Damien Neil, and Michael Stapelberg discovered that rsync daemons configured without chroot protection were exposed to a race condition on parent path components. A local attacker with write access to a module could possibly use this issue to overwrite files, obtain sensitive information, or escalate privileges. ( CVE-2026-29518 ) It was discovered that rsync did not properly validate a length value while sorting extended attributes. An attacker could possibly use this issue to cause a denial of service. ( CVE-2026-41035 ) It was discovered that rsync performed reverse-DNS lookups after chrooting in some daemon configurations. A remote attacker could possibly use this issue to bypass hostname-based access controls and access network services. ( CVE-2026-43617 ) Omar Elsayed discovered that rsync did not properly check for integer overflows while decoding compressed tokens. A remote attacker could possibly use this issue to obtain sensitive information. ( CVE-2026-43618 ) Andrew Tridgell discovered that rsync did not fully fix a symlink race condition in path-based system calls for daemons configured without chroot protection. A local attacker could possibly use this issue to overwrite files, obtain sensitive information, or escalate privileges. ( CVE-2026-43619 ) Pratham Gupta discovered that rsync did not properly validate an index while processing file lists. A remote attacker could possibly use this issue to cause rsync to crash, resulting in a denial of service. ( CVE-2026-43620 ) Michal Ruprich discovered that rsync contained an off-by-one error while handling HTTP proxy responses. An attacker able to intercept network communications or a malicious proxy server could possibly use this issue to cause a denial of service. ( CVE-2026-45232 ) --------------------------------------------------------------------------------- Update instructions The problem can be corrected by updating your system to the following package versions: Ubuntu Package Version Release 20.04 LTS rsync - 3.1.3-8ubuntu0.9+esm2 Ubuntu Pro Fix available with Ubuntu focal Pro . 18.04 LTS rsync - 3.1.2-2.1ubuntu1.6+esm4 Ubuntu Pro Fix available with bionic Ubuntu Pro . 16.04 LTS rsync - 3.1.1-3ubuntu1.3+esm6 Ubuntu Pro Fix available with Ubuntu xenial Pro via Legacy Support add-on. 14.04 LTS rsync - 3.1.0-2ubuntu0.4+esm4 Ubuntu Pro Fix available with Ubuntu trusty Pro via Legacy Support add-on. --------------------------------------------------------------------------------- References o https://launchpad.net/bugs/2155874 - --------------------------END INCLUDED TEXT---------------------- You have received this e-mail bulletin as a result of your organisation's registration with AUSCERT. 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