==========================================================================
Ubuntu Security Notice USN-8376-1
June 03, 2026

frr 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 FRR.

Software Description:
- frr: FRRouting suite of internet protocols

Details:

It was discovered that FRR incorrectly handled certain OSPF Traffic
Engineering and Segment Routing TLVs. An attacker could possibly use this
issue to cause FRR to crash, resulting in a denial of service.
(CVE-2026-28532)

It was discovered that FRR incorrectly handled certain BGP FlowSpec
components. An attacker could possibly use this issue to cause FRR to
crash, resulting in a denial of service. (CVE-2026-37457)

It was discovered that FRR did not properly validate certain MP_REACH_NLRI
messages. An authenticated user could possibly use this issue to cause FRR
to crash, resulting in a denial of service. (CVE-2026-37458)

It was discovered that FRR incorrectly handled processing certain BGP
UPDATE messages. An attacker could possibly use this issue to cause FRR to
crash, resulting in a denial of service. This issue only affected Ubuntu
25.04 and Ubuntu 25.10. (CVE-2026-37459)

Update instructions:

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

Ubuntu 26.04 LTS
  frr                             10.5.1-1ubuntu4.1

Ubuntu 25.10
  frr                             10.4.1-3ubuntu1.4

Ubuntu 24.04 LTS
  frr                             8.4.4-1.1ubuntu6.7

Ubuntu 22.04 LTS
  frr                             8.1-1ubuntu1.16

In general, a standard system update will make all the necessary changes.

References:
  https://ubuntu.com/security/notices/USN-8376-1
  CVE-2026-28532, CVE-2026-37457, CVE-2026-37458, CVE-2026-37459

Package Information:
  https://launchpad.net/ubuntu/+source/frr/10.5.1-1ubuntu4.1
  https://launchpad.net/ubuntu/+source/frr/10.4.1-3ubuntu1.4
  https://launchpad.net/ubuntu/+source/frr/8.4.4-1.1ubuntu6.7
  https://launchpad.net/ubuntu/+source/frr/8.1-1ubuntu1.16