CVE-2026-5265
Description
When generating an ICMP Destination Unreachable or Packet Too Big response, the handler copies a portion of the original packet into the ICMP error body using the IP header's self-declared total length (ip_tot_len for IPv4, ip6_plen for IPv6) without validating it against the actual packet buffer size. A VM can send a short packet with an inflated IP length field that triggers an ICMP error (e.g., by hitting a reject ACL), causing ovn-controller to read heap memory beyond the valid packet data and include it in the ICMP response sent back to the VM.
How to fix CVE-2026-5265
No fixed version has been published yet. Mitigate by removing the affected package or applying upstream guidance from the references below.
- —no fix listed
Is CVE-2026-5265 being exploited?
Low — EPSS is 0.6%, meaning exploitation activity has not been observed at scale.
Affected packages (1)
- from 0
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | MEDIUM6.5 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:H |