Ubuntu alert USN-8283-1 (rsync)

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noreply+usn-bot@canonical.com
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ubuntu-security-announce@lists.ubuntu.com
Subject:
             
 
[USN-8283-1] rsync vulnerabilities
Date:
             
 
Wed, 20 May 2026 13:48:27 +0000
Message-ID:
             
 
<E1wPhHf-0006up-N5@lists.ubuntu.com>
==========================================================================
Ubuntu Security Notice USN-8283-1
May 20, 2026

rsync vulnerabilities
==========================================================================

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

- Ubuntu 26.04 LTS
- Ubuntu 25.10
- Ubuntu 24.04 LTS
- Ubuntu 22.04 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. 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:

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

Ubuntu 26.04 LTS
  rsync                           3.4.1+ds1-7ubuntu0.2

Ubuntu 25.10
  rsync                           3.4.1+ds1-5ubuntu1.2

Ubuntu 24.04 LTS
  rsync                           3.2.7-1ubuntu1.4

Ubuntu 22.04 LTS
  rsync                           3.2.7-0ubuntu0.22.04.6

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-8283-1
  CVE-2025-10158, CVE-2026-29518, CVE-2026-41035, CVE-2026-43617,
  CVE-2026-43618, CVE-2026-43619, CVE-2026-43620, CVE-2026-45232

Package Information:
  https://launchpad.net/ubuntu/+source/rsync/3.4.1+ds1-7ubu...
  https://launchpad.net/ubuntu/+source/rsync/3.4.1+ds1-5ubu...
  https://launchpad.net/ubuntu/+source/rsync/3.2.7-1ubuntu1.4
  https://launchpad.net/ubuntu/+source/rsync/3.2.7-0ubuntu0...


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