rsync vulnerabilities

Summary

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. This issue only affected Ubuntu 22.04 LTS, Ubuntu 24.04 LTS, and Ubuntu 25.10. (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- Affected Ubuntu releases: 26.04, 25.10, 24.04, 22.04. CVEs: CVE-2026-43620, CVE-2026-43618, CVE-2026-43617, CVE-2026-45232, CVE-2026-43619, CVE-2026-29518, CVE-2026-41035, CVE-2025-10158.