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CVE Record

CVE-2026-5367: Ovn: ovn: information disclosure via crafted dhcpv6 packets

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.

HighCVSS 8.6Not KEV-listedUpdated
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Glexia's TakeAutomated analysishigh

Security readout for executives and security teams

Plain-English summary

OVN can disclose memory from the network controller when it receives malformed DHCPv6 traffic. In affected Red Hat Fast Datapath and one OpenShift OVN stream, a remote sender may read sensitive heap data back through a virtual machine port. The issue is confidentiality-focused: no integrity or availability impact is stated.

Executive priority

Treat this as a high-priority confidentiality risk for affected virtual networking platforms. It can leak sensitive controller heap memory without authentication, but available evidence does not show active exploitation. Patch affected OVN streams through Red Hat advisories on an accelerated maintenance timeline.

Technical view

CVE-2026-5367 is a CWE-130 length-handling flaw in OVN. Crafted DHCPv6 SOLICIT packets with an inflated Client ID length can make ovn-controller read beyond packet bounds and return heap memory to the sender's VM port. CVSS 3.1 is 8.6: network, low complexity, no privileges, no user interaction, scope changed, high confidentiality impact.

Likely exposure

Exposure is most likely where affected OVN package streams run in Red Hat Fast Datapath for RHEL 8, 9, or 10, or OpenShift Container Platform 4 with ovn23.06. Environments without OVN, without affected package streams, or using source-listed unaffected streams have lower indicated exposure.

Exploitation context

The source bundle does not show CISA KEV listing or active exploitation evidence. The vulnerability is remotely reachable in the stated model and requires crafted DHCPv6 SOLICIT traffic, but the provided sources do not include public weaponization details.

Researcher notes

Key constraints are source-limited: affected Red Hat package streams are named, but fixed versions and detailed remediation text are not in the bundle. The flaw is packet length validation around DHCPv6 Client ID handling, producing an out-of-bounds read and data disclosure to the attacker-controlled VM port.

Mitigation direction

  • Identify Red Hat Fast Datapath and OpenShift systems running OVN.
  • Map installed OVN package streams against the affected list.
  • Apply the relevant Red Hat RHSA updates for each affected stream.
  • Prioritize shared virtualization and tenant-facing network environments.
  • If updates are unavailable, follow current Red Hat vendor guidance.

Validation and detection

  • Confirm installed package names and versions on Fast Datapath hosts.
  • Check OpenShift OVN stream; ovn23.06 is listed affected.
  • Verify ovn22.06, ovn22.09, ovn22.12, and ovn23.03 OpenShift streams are listed unaffected.
  • Review network monitoring for anomalous DHCPv6 SOLICIT activity in OVN segments.
  • Document whether DHCPv6 is reachable from untrusted VM or tenant ports.
Prepared
Confidence
high
Sources
12

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.

ATT&CK lookup starting points

Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.

cwe · low confidence lookup

CWE-130: Exact CWE lookup

Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.

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description · low confidence lookup

Container behavior lookup

The affected technology mentions containers, so container-specific ATT&CK technique review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.

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cve · low confidence lookup

CVE-2026-5367 mapping review

Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.

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Vulnerability profileCVE Program record
Severity
High
CVSS
8.6 (3.1)
Known Exploited
No
Published

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N

Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

2CVSS vectors
7Timeline events
3ADP providers
13Source links

SSVC decision data

CISA-ADPCISA Coordinator
Timestamp
Version
2.0.3
Exploitation: noneAutomatable: yesTechnical Impact: partial

CVSS vector scores

2 official scores

We collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.

ScoreVersionSeverityVectorExploitImpactSource
8.6CVSS 3.1HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N3.94redhat
8.6CVSS 3.1HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N3.94redhat-SADP

Vulnerability scoring details

Base CVSS 3.1 score

8.6High
CVSS 3.1 vector shape for CVE-2026-5367Attack VectorAttack ComplexityPrivileges RequiredUser InteractionScopeConfidentiality ImpactIntegrity ImpactAvailability Impact

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N

Attack Vector
NetworkAdjacentLocalPhysical
Attack Complexity
LowHigh
Privileges Required
NoneLowHigh
User Interaction
NoneRequired
Scope
ChangedUnchanged
Confidentiality Impact
HighLowNone
Integrity Impact
HighLowNone
Availability Impact
HighLowNone

Vulnerability timeline

Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.

  1. CVE reservedCVE Program

    The CVE ID was reserved by the assigning CNA.

  2. ADP timelineredhat-SADP

    Reported to Red Hat.

  3. Source timelineredhat

    Reported to Red Hat.

  4. ADP timelineredhat-SADP

    Made public.

  5. Source timelineredhat

    Made public.

  6. CVE publishedCVE Program

    The CVE record was published.

  7. CVE updatedCVE Program

    The CVE record metadata indicates this as the latest update time.

ADP provider summaries

CVECVE Program Container
CISA-ADPCISA ADP Vulnrichment
other:ssvc
redhat-SADPovn: OVN: Information disclosure via crafted DHCPv6 packets
other:Red Hat severity ratingcvssV3_1
  • 2026-04-07T08:10:53.507Z: Reported to Red Hat.
  • 2026-04-13T00:00:00.000Z: Made public.

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
Red HatFast Datapath for Red Hat Enterprise Linux 10ovn25.03, 0:25.03.2-100.el10fdpaffected
Red HatFast Datapath for Red Hat Enterprise Linux 10ovn25.09, 0:25.09.2-103.el10fdpaffected
Red HatFast Datapath for Red Hat Enterprise Linux 8ovn-2021, 0:21.12.0-145.el8fdpaffected
Red HatFast Datapath for Red Hat Enterprise Linux 8ovn23.06, 0:23.06.4-30.el8fdpaffected
Red HatFast Datapath for Red Hat Enterprise Linux 9ovn23.06, 0:23.06.4-30.el9fdpaffected
Red HatFast Datapath for Red Hat Enterprise Linux 9ovn23.09, 0:23.09.6-16.el9fdpaffected
Red HatFast Datapath for Red Hat Enterprise Linux 9ovn24.03, 0:24.03.7-82.el9fdpaffected
Red HatFast Datapath for Red Hat Enterprise Linux 9ovn25.03, 0:25.03.2-100.el9fdpaffected
Red HatFast Datapath for Red Hat Enterprise Linux 9ovn25.09, 0:25.09.2-103.el9fdpaffected
Red HatFast Datapath for RHEL 8ovn2.11unaffected
Red HatFast Datapath for RHEL 8ovn2.12unaffected
Red HatFast Datapath for RHEL 8ovn2.13unaffected
Red HatFast Datapath for RHEL 8ovn23.03affected
Red HatFast Datapath for RHEL 9ovn-2021affected
Red HatFast Datapath for RHEL 9ovn23.03affected
Red HatRed Hat OpenShift Container Platform 4ovn22.06unaffected
Red HatRed Hat OpenShift Container Platform 4ovn22.09unaffected
Red HatRed Hat OpenShift Container Platform 4ovn22.12unaffected
Red HatRed Hat OpenShift Container Platform 4ovn23.03unaffected
Red HatRed Hat OpenShift Container Platform 4ovn23.06affected
Red HatRed Hat OpenShift Container Platform 4ovn23.09unaffected
Red HatRed Hat OpenShift Container Platform 4ovn24.03affected
Red HatRed Hat OpenShift Container Platform 4ovn24.09unaffected
Red HatRed Hat OpenShift Container Platform 4ovn25.03affected
Weakness

CWE details

CWE-130

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.

CWE-130 · source CWE mapping

Improper Handling of Length Parameter Inconsistency

Improper Handling of Length Parameter Inconsistency represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.

Open CWE intelligenceSame-CWE CVEs