CVE-2026-5265
CWE-130Published: April 24, 2026· Updated: Apr 29, 2026
Official 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.
Technical Analysis
CVE-2026-5265 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.
A successful exploit results in availability disruption (denial of service), with a CVSS base score of 6.5.
CVSS v3.1 Vector Breakdown
Exploit & PoC Resources
All References (11)
Quick Facts
Related CVEs (CWE-130)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2026-5265 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts