Home / mailings

PDF

[USN-8349-1] rsync vulnerabilities

Posted on 01 June 2026
Ubuntu Security

==========================================================================Ubuntu Security Notice USN-8349-1
June 01, 2026

rsync vulnerabilities
==========================================================================
A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 20.04 LTS
- Ubuntu 18.04 LTS
- Ubuntu 16.04 LTS
- Ubuntu 14.04 LTS

Summary:

Several security issues were fixed in rsync.

Software Description:
- 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. (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 20.04 LTS
rsync 3.1.3-8ubuntu0.9+esm1
Available with Ubuntu Pro

Ubuntu 18.04 LTS
rsync 3.1.2-2.1ubuntu1.6+esm3
Available with Ubuntu Pro

Ubuntu 16.04 LTS
rsync 3.1.1-3ubuntu1.3+esm5
Available with Ubuntu Pro

Ubuntu 14.04 LTS
rsync 3.1.0-2ubuntu0.4+esm3
Available with Ubuntu Pro

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.

References:
https://ubuntu.com/security/notices/USN-8349-1
CVE-2025-10158, CVE-2026-29518, CVE-2026-41035, CVE-2026-43617,
CVE-2026-43618, CVE-2026-43619, CVE-2026-43620, CVE-2026-45232

--===============3925980428386646434==Content-Type: application/pgp-signature; name="signature.asc"
Content-Description: OpenPGP digital signature

 

TOP