CVE-2026-5265Ovn: ovn: heap over-read in icmp error response generation

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.

Timeline

Scores

EPSS (exploitation in 30 days)

0.63% · top 49% of all CVEs (13 Nov 2026)

CISA SSVC

Exploitation: none · Automatable: no · Technical impact: partial

The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 6.5.

Affected products

• Red Hat · Fast Datapath for Red Hat Enterprise Linux 10

  • unaffected 0:25.03.2-100.el10fdp – < *

• Red Hat · Fast Datapath for Red Hat Enterprise Linux 10

  • unaffected 0:25.09.2-103.el10fdp – < *

• Red Hat · Fast Datapath for Red Hat Enterprise Linux 8

  • unaffected 0:21.12.0-145.el8fdp – < *

• Red Hat · Fast Datapath for Red Hat Enterprise Linux 8

  • unaffected 0:23.06.4-30.el8fdp – < *

• Red Hat · Fast Datapath for Red Hat Enterprise Linux 9

  • unaffected 0:23.06.4-30.el9fdp – < *

• Red Hat · Fast Datapath for Red Hat Enterprise Linux 9

  • unaffected 0:23.09.6-16.el9fdp – < *

• Red Hat · Fast Datapath for Red Hat Enterprise Linux 9

  • unaffected 0:24.03.7-82.el9fdp – < *

• Red Hat · Fast Datapath for Red Hat Enterprise Linux 9

  • unaffected 0:25.03.2-100.el9fdp – < *

• Red Hat · Fast Datapath for Red Hat Enterprise Linux 9

  • unaffected 0:25.09.2-103.el9fdp – < *

• Red Hat · Fast Datapath for RHEL 7

  All versions: affected

• Red Hat · Fast Datapath for RHEL 7

  All versions: affected

• Red Hat · Fast Datapath for RHEL 7

  All versions: affected

• Red Hat · Fast Datapath for RHEL 8

  All versions: affected

• Red Hat · Fast Datapath for RHEL 8

  All versions: affected

• Red Hat · Fast Datapath for RHEL 8

  All versions: affected

• Red Hat · Fast Datapath for RHEL 8

  All versions: affected

• Red Hat · Fast Datapath for RHEL 8

  All versions: affected

• Red Hat · Fast Datapath for RHEL 8

  All versions: affected

• Red Hat · Fast Datapath for RHEL 8

  All versions: affected

• Red Hat · Fast Datapath for RHEL 8

  All versions: affected

• Red Hat · Fast Datapath for RHEL 9

  All versions: affected

• Red Hat · Fast Datapath for RHEL 9

  All versions: affected

• Red Hat · Fast Datapath for RHEL 9

  All versions: affected

• Red Hat · Fast Datapath for RHEL 9

  All versions: affected

• Red Hat · Fast Datapath for RHEL 9

  All versions: affected

• Red Hat · Fast Datapath for RHEL 9

  All versions: affected

• Red Hat · Fast Datapath for RHEL 9

  All versions: affected

What to do

Workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.

Sources

The same CVE in the primary databases and aggregators, to check against.

• CVE.org record (opens in a new tab)
• CVE List JSON (GitHub) (opens in a new tab)
• NVD (opens in a new tab)
• FIRST EPSS (opens in a new tab)
• EUVD EUVD-2026-25420 (opens in a new tab)
• OSV.dev (opens in a new tab)
• GitHub Advisories (opens in a new tab)
• CIRCL Vulnerability-Lookup (opens in a new tab)

Badge for a README or a ticket

[![CVE-2026-5265](https://cveledger.app/badge/CVE-2026-5265.svg)](https://cveledger.app/cve/CVE-2026-5265)

Record last updated 17 Jun 2026, 22:00 UTC.