Ovn: ovn: information disclosure via crafted dhcpv6 packets
Published Apr 24, 2026
8.6
HIGHCVSS 3.1
EPSS 0.88%
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.
Affected products
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | |||
|---|---|---|---|---|---|---|
| Red Hat | Fast Datapath for RHEL 8 | affected |
| |||
| Red Hat | Fast Datapath for RHEL 9 | affected |
| |||
| Red Hat | Red Hat OpenShift Container Platform 4 | affected |
|
No data.
No data.
Fast Datapath for Red Hat Enterprise Linux 10
ovn25.03-0:25.03.2-100.el10fdp
Fixed · RHSA-2026:22110
Fast Datapath for Red Hat Enterprise Linux 10
ovn25.09-0:25.09.2-103.el10fdp
Fixed · RHSA-2026:22111
Fast Datapath for Red Hat Enterprise Linux 8
ovn-2021-0:21.12.0-145.el8fdp
Fixed · RHSA-2026:11694
Fast Datapath for Red Hat Enterprise Linux 8
ovn23.06-0:23.06.4-30.el8fdp
Fixed · RHSA-2026:11695
Fast Datapath for Red Hat Enterprise Linux 9
ovn23.06-0:23.06.4-30.el9fdp
Fixed · RHSA-2026:11696
Fast Datapath for Red Hat Enterprise Linux 9
ovn23.09-0:23.09.6-16.el9fdp
Fixed · RHSA-2026:11698
Fast Datapath for Red Hat Enterprise Linux 9
ovn24.03-0:24.03.7-82.el9fdp
Fixed · RHSA-2026:11700
Fast Datapath for Red Hat Enterprise Linux 9
ovn25.03-0:25.03.2-100.el9fdp
Fixed · RHSA-2026:11701
Fast Datapath for Red Hat Enterprise Linux 9
ovn25.09-0:25.09.2-103.el9fdp
Fixed · RHSA-2026:11702
Fast Datapath for RHEL 8
ovn2.11
Not affected
Fast Datapath for RHEL 8
ovn2.12
Not affected
Fast Datapath for RHEL 8
ovn2.13
Not affected
Fast Datapath for RHEL 8
ovn23.03
Affected
Fast Datapath for RHEL 9
ovn-2021
Affected
Fast Datapath for RHEL 9
ovn23.03
Affected
Red Hat OpenShift Container Platform 4
ovn22.06
Not affected
Red Hat OpenShift Container Platform 4
ovn22.09
Not affected
Red Hat OpenShift Container Platform 4
ovn22.12
Not affected
Red Hat OpenShift Container Platform 4
ovn23.03
Not affected
Red Hat OpenShift Container Platform 4
ovn23.06
Affected
Red Hat OpenShift Container Platform 4
ovn23.09
Not affected
Red Hat OpenShift Container Platform 4
ovn24.03
Affected
Red Hat OpenShift Container Platform 4
ovn24.09
Affected
Red Hat OpenShift Container Platform 4
ovn25.03
Affected
| Product | Package | State | Advisory |
|---|---|---|---|
| Fast Datapath for Red Hat Enterprise Linux 10 | ovn25.03-0:25.03.2-100.el10fdp | Fixed | RHSA-2026:22110 |
| Fast Datapath for Red Hat Enterprise Linux 10 | ovn25.09-0:25.09.2-103.el10fdp | Fixed | RHSA-2026:22111 |
| Fast Datapath for Red Hat Enterprise Linux 8 | ovn-2021-0:21.12.0-145.el8fdp | Fixed | RHSA-2026:11694 |
| Fast Datapath for Red Hat Enterprise Linux 8 | ovn23.06-0:23.06.4-30.el8fdp | Fixed | RHSA-2026:11695 |
| Fast Datapath for Red Hat Enterprise Linux 9 | ovn23.06-0:23.06.4-30.el9fdp | Fixed | RHSA-2026:11696 |
| Fast Datapath for Red Hat Enterprise Linux 9 | ovn23.09-0:23.09.6-16.el9fdp | Fixed | RHSA-2026:11698 |
| Fast Datapath for Red Hat Enterprise Linux 9 | ovn24.03-0:24.03.7-82.el9fdp | Fixed | RHSA-2026:11700 |
| Fast Datapath for Red Hat Enterprise Linux 9 | ovn25.03-0:25.03.2-100.el9fdp | Fixed | RHSA-2026:11701 |
| Fast Datapath for Red Hat Enterprise Linux 9 | ovn25.09-0:25.09.2-103.el9fdp | Fixed | RHSA-2026:11702 |
| Fast Datapath for RHEL 8 | ovn2.11 | Not affected | n/a |
| Fast Datapath for RHEL 8 | ovn2.12 | Not affected | n/a |
| Fast Datapath for RHEL 8 | ovn2.13 | Not affected | n/a |
| Fast Datapath for RHEL 8 | ovn23.03 | Affected | n/a |
| Fast Datapath for RHEL 9 | ovn-2021 | Affected | n/a |
| Fast Datapath for RHEL 9 | ovn23.03 | Affected | n/a |
| Red Hat OpenShift Container Platform 4 | ovn22.06 | Not affected | n/a |
| Red Hat OpenShift Container Platform 4 | ovn22.09 | Not affected | n/a |
| Red Hat OpenShift Container Platform 4 | ovn22.12 | Not affected | n/a |
| Red Hat OpenShift Container Platform 4 | ovn23.03 | Not affected | n/a |
| Red Hat OpenShift Container Platform 4 | ovn23.06 | Affected | n/a |
| Red Hat OpenShift Container Platform 4 | ovn23.09 | Not affected | n/a |
| Red Hat OpenShift Container Platform 4 | ovn24.03 | Affected | n/a |
| Red Hat OpenShift Container Platform 4 | ovn24.09 | Affected | n/a |
| Red Hat OpenShift Container Platform 4 | ovn25.03 | Affected | n/a |
No package ranges for this CVE.
Remediation
Vendor solution
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.
Red Hat statement
An Important information disclosure flaw exists in OVN (Open Virtual Network) where a remote attacker can send specially crafted DHCPv6 SOLICIT packets to the `ovn-controller`. This can lead to an out-of-bounds read, disclosing sensitive heap memory information back to the attacker's virtual machine port. This vulnerability affects OVN deployments where DHCPv6 is enabled for logical switch ports.
Red Hat mitigation
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.
Metrics
No CVSS v4.0 score for this CVE.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N
No CVSS v3.0 score for this CVE.
No CVSS v2.0 score for this CVE.
This CVE is not in the KEV list.
CISA SSVC (Vulnrichment)
Stakeholder-Specific Vulnerability Categorization from CISA ADP.
Exploitation
NoneAutomatable
YesTechnical Impact
PartialDecision
n/aAssessed Apr 24, 2026 · SSVC 2.0.3
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 2, 2026.
Score over time
Apr–Oct 2026- EPSS v4
- EPSS v5
Percentile over time
- EPSS v4
- EPSS v5
Table of values (3 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 2, 2026 | 0.88% (0.00879) | 57.63th | v5 (v2026.06.15) |
| Jun 15, 2026 | 0.87% (0.00868) | 53.86th | v5 (v2026.06.15) |
| Apr 25, 2026 | 0.03% (0.00031) | 8.83th | v4 (v2025.03.14) |
References (16)
- http://www.openwall.com/lists/oss-security/2026/04/20/3
- http://www.openwall.com/lists/oss-security/2026/04/20/5
- https://access.redhat.com/errata/RHSA-2026:11694 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:11695 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:11696 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:11698 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:11700 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:11701 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:11702 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:22110 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:22111 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/security/cve/CVE-2026-5367 vdb-entryx_refsource_REDHATVendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=2455863 issue-trackingx_refsource_REDHATIssue Tracking
- https://nvd.nist.gov/vuln/detail/CVE-2026-5367
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-5367.json
- https://www.cve.org/CVERecord?id=CVE-2026-5367
Change history (0)
No recorded changes yet.