SB2026072839 - Improper input validation in Linux kernel bridge
Published: July 28, 2026
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Improper input validation (CVE-ID: CVE-2026-64537)
CWE-ID: CWE-20 - Improper input validation
CVSSv4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to improper input validation in the bridge cfm ccm transmission logic when configuring an invalid ccm interval. A local user can set an invalid expiration interval to trigger a tight workqueue loop and exhaust memory to cause a denial of service.
The issue can result in immediate re-arming of delayed work and repeated skb allocations until out-of-memory conditions occur.
Remediation
Install update from vendor's website.
References
- https://git.kernel.org/stable/c/2870056a78961e0fecd652362ee9d3fcfd24a8a6
- https://git.kernel.org/stable/c/53788b134519e995699ea3721969c96a08d64575
- https://git.kernel.org/stable/c/865643640b5b5c4579b32d7a55ac9ad648362eaa
- https://git.kernel.org/stable/c/a090880c1f544589427e5b7050c40fb211ccecb4
- https://git.kernel.org/stable/c/b42aeb58317f12024734759ff745856b53948873
- https://git.kernel.org/stable/c/f0f5eb59a97ece0d85de8cfa95dc18c609302a8b
- https://git.kernel.org/stable/c/f3e02edd8322b31b8e6517faa6ba053bf29d1e26