---
id: CVE-2026-52931
title: 'batman-adv: tp_meter: avoid use of uninit sender vars'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  batman-adv: tp_meter: avoid use of uninit sender vars

  batadv_tp_recv_ack() and batadv_tp_stop() are only valid for tp_vars in the
  BATADV_TP_SENDER role. When called wi…
severity: critical
cvss: 9.8
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'
cvssSource: cna
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 33a3bb4a3345bb511f9c69c913da95d4693e2a4e <
    0e388af04b3958b178a1b979527f93eb46ea1fee
  - >-
    Linux >= 33a3bb4a3345bb511f9c69c913da95d4693e2a4e <
    1a21c055f66e78973712a4a1be2a554f1ee2e4f4
  - >-
    Linux >= 33a3bb4a3345bb511f9c69c913da95d4693e2a4e <
    9884c9c02d3c90e9215db3c5128f59045d20ae91
  - >-
    Linux >= 33a3bb4a3345bb511f9c69c913da95d4693e2a4e <
    53f931e0146ae5bdab4cba302646827d06b3794b
  - >-
    Linux >= 33a3bb4a3345bb511f9c69c913da95d4693e2a4e <
    ecdaa3e4d91040206afe21bc8a0d1198a0971ff3
  - >-
    Linux >= 33a3bb4a3345bb511f9c69c913da95d4693e2a4e <
    dc2ae5fbd2dadc26735092f140b246841d969a11
  - >-
    Linux >= 33a3bb4a3345bb511f9c69c913da95d4693e2a4e <
    85397e48afe6be83ffca5ad3f4792296bfc81d3d
  - >-
    Linux >= 33a3bb4a3345bb511f9c69c913da95d4693e2a4e <
    6c65cf23d4c6170fcf5714c32aa64689718cb142
  - Linux 4.8
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: total
  timestamp: '2026-10-16T15:22:56.523989Z'
published: '2026-06-24'
updated: '2026-10-16'
sourceUpdated: '2026-10-16T15:31:20.602Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-52931'
references:
  - url: 'https://git.kernel.org/stable/c/0e388af04b3958b178a1b979527f93eb46ea1fee'
  - url: 'https://git.kernel.org/stable/c/1a21c055f66e78973712a4a1be2a554f1ee2e4f4'
  - url: 'https://git.kernel.org/stable/c/9884c9c02d3c90e9215db3c5128f59045d20ae91'
  - url: 'https://git.kernel.org/stable/c/53f931e0146ae5bdab4cba302646827d06b3794b'
  - url: 'https://git.kernel.org/stable/c/ecdaa3e4d91040206afe21bc8a0d1198a0971ff3'
  - url: 'https://git.kernel.org/stable/c/dc2ae5fbd2dadc26735092f140b246841d969a11'
  - url: 'https://git.kernel.org/stable/c/85397e48afe6be83ffca5ad3f4792296bfc81d3d'
  - url: 'https://git.kernel.org/stable/c/6c65cf23d4c6170fcf5714c32aa64689718cb142'
tags:
  - cve.org
epss: 0.00399
epssPercentile: 0.32546
ingestedAt: '2026-10-16T17:24:46.720Z'
---

## Overview

In the Linux kernel, the following vulnerability has been resolved:

batman-adv: tp_meter: avoid use of uninit sender vars

batadv_tp_recv_ack() and batadv_tp_stop() are only valid for tp_vars in the
BATADV_TP_SENDER role. When called with a BATADV_TP_RECEIVER role, it
proceeds to read sender-only members that were never initialized, leading
to undefined behavior.

This can be triggered when a node that is currently acting as a receiver in
an ongoing tp_meter session receives a malicious ACK packet.

Guard against this by checking tp_vars->role immediately after the
lookup and bailing out if it is not BATADV_TP_SENDER, before any of
those members are accessed.

## Affected

- `Linux >= 33a3bb4a3345bb511f9c69c913da95d4693e2a4e < 0e388af04b3958b178a1b979527f93eb46ea1fee`
- `Linux >= 33a3bb4a3345bb511f9c69c913da95d4693e2a4e < 1a21c055f66e78973712a4a1be2a554f1ee2e4f4`
- `Linux >= 33a3bb4a3345bb511f9c69c913da95d4693e2a4e < 9884c9c02d3c90e9215db3c5128f59045d20ae91`
- `Linux >= 33a3bb4a3345bb511f9c69c913da95d4693e2a4e < 53f931e0146ae5bdab4cba302646827d06b3794b`
- `Linux >= 33a3bb4a3345bb511f9c69c913da95d4693e2a4e < ecdaa3e4d91040206afe21bc8a0d1198a0971ff3`
- `Linux >= 33a3bb4a3345bb511f9c69c913da95d4693e2a4e < dc2ae5fbd2dadc26735092f140b246841d969a11`
- `Linux >= 33a3bb4a3345bb511f9c69c913da95d4693e2a4e < 85397e48afe6be83ffca5ad3f4792296bfc81d3d`
- `Linux >= 33a3bb4a3345bb511f9c69c913da95d4693e2a4e < 6c65cf23d4c6170fcf5714c32aa64689718cb142`
- `Linux 4.8`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.