CVE-2026-5265: ovn
Vulnerability summary
CVE-2026-5265 is a medium (CVSS 6.5) vulnerability in ovn. EPSS estimates a 0.66% chance of exploitation in the next 30 days, higher than 50.8% of scored vulnerabilities.
Advisory lineage
Upstream 0 · Downstream 19 · Related 10Timeline
- 24-04-2026PublishedVulnerability first disclosed.
- 17-06-2026Last modifiedVulnerability information updated.
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.
CVSS metrics
4 scores · 4 sources · 1 version- OSV · UbuntuEcosystem advisory · calculated6.5MediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:H
- OSV · DebianEcosystem advisory · calculated6.5MediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:H
- NVDNIST6.5MediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:H
EPSS trend
Probability
0.66%
Chance of exploitation in the next 30 days
Percentile
51%
Versus all other CVEs
30-day change
+0.03 pp
From 0.63% on 21-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Debian1 product
- ovnAll versions (No fix recorded) | < 26.03.0-4
Ubuntu1 product
- ovnAll versions (No fix recorded)
2 vendors · 2 products
