USN-8283-1: rsync vulnerabilities

Publication date

20 May 2026

Overview

Several security issues were fixed in rsync.


Packages

  • rsync - fast, versatile, remote (and local) file-copying tool

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. 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. (

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-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

In general, a standard system update will make all the necessary changes. After a standard system update you need to restart rsync daemons if configured to make all the necessary changes.

Learn more about how to get the fixes.

The problem can be corrected by updating your system to the following package versions:

Ubuntu Release Package Version
26.04 LTS resolute rsync –  3.4.1+ds1-7ubuntu0.2
25.10 questing rsync –  3.4.1+ds1-5ubuntu1.2
24.04 LTS noble rsync –  3.2.7-1ubuntu1.4
22.04 LTS jammy rsync –  3.2.7-0ubuntu0.22.04.6

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