Ovn: ovn: information disclosure via crafted dhcpv6 packets

Description

A flaw was found in OVN (Open Virtual Network). A remote attacker, by sending crafted DHCPv6 (Dynamic Host Configuration Protocol for IPv6) SOLICIT packets with an inflated Client ID length, could cause the ovn-controller to read beyond the bounds of a packet. This out-of-bounds read can lead to the disclosure of sensitive information stored in heap memory, which is then returned to the attacker's virtual machine port.

Timeline

Scores

EPSS (exploitation in 30 days)

0.87% · top 41% of all CVEs (11 Nov 2026)

CISA SSVC

Exploitation: none · Automatable: yes · Technical impact: partial

The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.6.

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 8

  All versions: unaffected

• Red Hat · Fast Datapath for RHEL 8

  All versions: unaffected

• Red Hat · Fast Datapath for RHEL 8

  All versions: unaffected

• 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 · Red Hat OpenShift Container Platform 4

  All versions: unaffected

• Red Hat · Red Hat OpenShift Container Platform 4

  All versions: unaffected

• Red Hat · Red Hat OpenShift Container Platform 4

  All versions: unaffected

• Red Hat · Red Hat OpenShift Container Platform 4

  All versions: unaffected

• Red Hat · Red Hat OpenShift Container Platform 4

  All versions: affected

• Red Hat · Red Hat OpenShift Container Platform 4

  All versions: unaffected

• Red Hat · Red Hat OpenShift Container Platform 4

  All versions: affected

• Red Hat · Red Hat OpenShift Container Platform 4

  All versions: affected

• Red Hat · Red Hat OpenShift Container Platform 4

  All versions: affected

What to do

Workaround: The only potential mitigation is to disable the DHCPv6 feature for workloads attached to OVN logical ports, e.g.: ovn-nbctl clear logical_switch_port <workload-port> dhcpv6_options. We do not recommend mitigating the vulnerability this way because it will also disable legitimate DHCPv6 traffic originating from workloads connected to logical switch ports.

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-2026-25421 (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-2026-5367](https://cveledger.app/badge/CVE-2026-5367.svg)](https://cveledger.app/cve/CVE-2026-5367)

Record last updated 25 Aug 2026, 12:05 UTC.