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CVE Record

CVE-2026-46238: batman-adv: stop caching unowned originator pointers in BAT IV

In the Linux kernel, the following vulnerability has been resolved: batman-adv: stop caching unowned originator pointers in BAT IV BAT IV keeps the last-hop neighbor address in each neigh_node, but some paths also cache an originator pointer derived from a temporary lookup. That pointer is not owned by the neigh_node and may no longer refer to a live originator entry after purge handling runs. Stop storing the auxiliary originator pointer in the BAT IV neighbor state. When BAT IV needs the neighbor originator data, resolve it from the stored neighbor address and drop the reference again after use. [sven: avoid bonding logic for outgoing OGM]

HighCVSS 8.8Not KEV-listedUpdated
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Glexia's TakeAutomated analysishigh

Security readout for executives and security teams

Plain-English summary

A Linux mesh-networking component can retain a reference to an object after that object is removed. Subsequent use may corrupt kernel behavior, with the supplied CVSS assessment indicating possible confidentiality, integrity, and availability impact. Risk is concentrated on systems using batman-adv’s BATMAN IV mode and reachable from an adjacent network.

Executive priority

Treat this as an accelerated patching priority where BATMAN IV is operational, especially on shared or untrusted adjacent networks. Validate actual feature use before escalating broadly because general Linux presence alone does not establish practical reachability. Request distribution-specific guidance where the supplied version list cannot conclusively establish fixed package status.

Technical view

BATMAN IV neighbor state cached an originator pointer obtained through a temporary lookup without owning its lifetime. Purge processing could remove the originator, leaving the cached pointer referencing a non-live entry. The fix removes that pointer and resolves originator data from the stored neighbor address when needed, releasing each acquired reference afterward. The sources do not document the precise failure manifestation.

Likely exposure

Potentially exposed assets are Linux systems containing affected kernel code and actively using batman-adv with BATMAN IV. The adjacent-network vector reduces internet-wide exposure but matters in shared, wireless, layer-2, or mesh environments. The supplied version data is not sufficiently clear for determining distribution-specific package status without vendor confirmation.

Exploitation context

The supplied CVSS vector describes adjacent access, low complexity, no privileges, and no user interaction. CISA KEV status is false, and the sources provide no evidence of active exploitation or a public proof of concept. High confidentiality, integrity, and availability impacts are CVSS-assessed potential outcomes, not documented observed attacks.

Researcher notes

The defect is a lifetime-management error involving an unowned originator pointer surviving purge handling. Upstream remediation replaces persistent pointer caching with address-based lookup and balanced reference release. No CWE, trigger sequence, crash evidence, exploit primitive, or demonstrated impact is provided, so exploitability beyond the CVSS assessment remains unverified.

Mitigation direction

  • Apply a vendor-supported kernel update containing the applicable batman-adv stable fix, then reboot into the updated kernel.
  • Prioritize systems actively using batman-adv BATMAN IV on networks accessible to untrusted adjacent devices.
  • Consult the Linux distribution or appliance vendor for package-specific fixed versions and supported interim guidance.
  • If updates are delayed, assess whether batman-adv can be safely removed from service without disrupting required mesh networking.

Validation and detection

  • Inventory kernel versions and identify hosts or appliances using batman-adv BATMAN IV.
  • Compare deployed vendor packages against advisories or the applicable upstream stable fix commit.
  • Confirm updated systems booted the intended fixed kernel rather than retaining an older running kernel.
  • Review kernel and networking telemetry for abnormal batman-adv faults, crashes, or instability; absence does not prove safety.
Prepared
Confidence
medium
Sources
10

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

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CVE-2026-46238 mapping review

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Vulnerability profileCVE Program record
Severity
High
CVSS
8.8 (3.1)
Known Exploited
No
Published

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

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.

1CVSS vectors
3Timeline events
0ADP providers
9Source links

CVSS vector scores

1 official score

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
8.8CVSS 3.1HighCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H2.85.9Linux

Vulnerability scoring details

Base CVSS 3.1 score

8.8High
CVSS 3.1 vector shape for CVE-2026-46238Attack VectorAttack ComplexityPrivileges RequiredUser InteractionScopeConfidentiality ImpactIntegrity ImpactAvailability Impact

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

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. CVE publishedCVE Program

    The CVE record was published.

  3. CVE updatedCVE Program

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

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
LinuxLinuxc6c8fea29769d998d94fcec9b9f14d4b52b349d3, c6c8fea29769d998d94fcec9b9f14d4b52b349d3, c6c8fea29769d998d94fcec9b9f14d4b52b349d3, c6c8fea29769d998d94fcec9b9f14d4b52b349d3, c6c8fea29769d998d94fcec9b9f14d4b52b349d3, c6c8fea29769d998d94fcec9b9f14d4b52b349d3, c6c8fea29769d998d94fcec9b9f14d4b52b349d3, c6c8fea29769d998d94fcec9b9f14d4b52b349d3unaffected
LinuxLinux2.6.38, 0, 5.10.258, 5.15.209, 6.1.175, 6.6.140, 6.12.90, 6.18.32, 7.0.9, 7.1affected
Weakness

CWE details

No CWE listed

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