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.
References10
- access.redhat.com/errata/RHSA-2026:11694
- access.redhat.com/errata/RHSA-2026:11695
- access.redhat.com/errata/RHSA-2026:11696
- access.redhat.com/errata/RHSA-2026:11698
- access.redhat.com/errata/RHSA-2026:11700
- access.redhat.com/errata/RHSA-2026:11701
- access.redhat.com/errata/RHSA-2026:11702
- access.redhat.com/errata/RHSA-2026:22110
- access.redhat.com/errata/RHSA-2026:22111
- access.redhat.com/security/cve/CVE-2026-5265
Metrics
- CVSS 3.1
-
6.5
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:H - EPSS — exploit probability
- 1% percentile: 51 · as of 13 November 2026
- CWE
- CWE-130
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