---
id: CVE-2026-31512
title: >-
  Bluetooth: L2CAP: Validate PDU length before reading SDU length in
  l2cap_ecred_data_rcv()
summary: >-
  In the Linux kernel, the following vulnerability has been resolved:


  Bluetooth: L2CAP: Validate PDU length before reading SDU length in
  l2cap_ecred_data_rcv()


  l2cap_ecred_data_rcv() reads the SDU length field from skb->data using

  get_un…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= aac23bf636593cc2d67144aed373a46a1a5f76b1 <
    cef09691cfb61f6c91cc27c3d69634f81c8ab949
  - >-
    Linux >= aac23bf636593cc2d67144aed373a46a1a5f76b1 <
    3340be2bafdcc806f048273ea6d8e82a6597aa1b
  - >-
    Linux >= aac23bf636593cc2d67144aed373a46a1a5f76b1 <
    e47315b84d0eb188772c3ff5cf073cdbdefca6b4
  - >-
    Linux >= aac23bf636593cc2d67144aed373a46a1a5f76b1 <
    477ad4976072056c348937e94f24583321938df4
  - >-
    Linux >= aac23bf636593cc2d67144aed373a46a1a5f76b1 <
    40c7f7eea2f4d9cb0b3e924254c8c9053372168f
  - >-
    Linux >= aac23bf636593cc2d67144aed373a46a1a5f76b1 <
    8c96f3bd4ae0802db90630be8e9851827e9c9209
  - >-
    Linux >= aac23bf636593cc2d67144aed373a46a1a5f76b1 <
    5ad981249be52f5e4e92e0e97b436b569071cb86
  - >-
    Linux >= aac23bf636593cc2d67144aed373a46a1a5f76b1 <
    c65bd945d1c08c3db756821b6bf9f1c4a77b29c6
  - Linux 3.14
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-11-05T21:36:21.853077Z'
published: '2026-04-22'
updated: '2026-11-05'
sourceUpdated: '2026-11-05T21:45:04.404Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-31512'
references:
  - url: 'https://git.kernel.org/stable/c/cef09691cfb61f6c91cc27c3d69634f81c8ab949'
  - url: 'https://git.kernel.org/stable/c/3340be2bafdcc806f048273ea6d8e82a6597aa1b'
  - url: 'https://git.kernel.org/stable/c/e47315b84d0eb188772c3ff5cf073cdbdefca6b4'
  - url: 'https://git.kernel.org/stable/c/477ad4976072056c348937e94f24583321938df4'
  - url: 'https://git.kernel.org/stable/c/40c7f7eea2f4d9cb0b3e924254c8c9053372168f'
  - url: 'https://git.kernel.org/stable/c/8c96f3bd4ae0802db90630be8e9851827e9c9209'
  - url: 'https://git.kernel.org/stable/c/5ad981249be52f5e4e92e0e97b436b569071cb86'
  - url: 'https://git.kernel.org/stable/c/c65bd945d1c08c3db756821b6bf9f1c4a77b29c6'
tags:
  - cve.org
epss: 0.00123
epssPercentile: 0.02047
ingestedAt: '2026-11-05T23:41:31.981Z'
---

## Overview

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

Bluetooth: L2CAP: Validate PDU length before reading SDU length in l2cap_ecred_data_rcv()

l2cap_ecred_data_rcv() reads the SDU length field from skb->data using
get_unaligned_le16() without first verifying that skb contains at least
L2CAP_SDULEN_SIZE (2) bytes. When skb->len is less than 2, this reads
past the valid data in the skb.

The ERTM reassembly path correctly calls pskb_may_pull() before reading
the SDU length (l2cap_reassemble_sdu, L2CAP_SAR_START case). Apply the
same validation to the Enhanced Credit Based Flow Control data path.

## Affected

- `Linux >= aac23bf636593cc2d67144aed373a46a1a5f76b1 < cef09691cfb61f6c91cc27c3d69634f81c8ab949`
- `Linux >= aac23bf636593cc2d67144aed373a46a1a5f76b1 < 3340be2bafdcc806f048273ea6d8e82a6597aa1b`
- `Linux >= aac23bf636593cc2d67144aed373a46a1a5f76b1 < e47315b84d0eb188772c3ff5cf073cdbdefca6b4`
- `Linux >= aac23bf636593cc2d67144aed373a46a1a5f76b1 < 477ad4976072056c348937e94f24583321938df4`
- `Linux >= aac23bf636593cc2d67144aed373a46a1a5f76b1 < 40c7f7eea2f4d9cb0b3e924254c8c9053372168f`
- `Linux >= aac23bf636593cc2d67144aed373a46a1a5f76b1 < 8c96f3bd4ae0802db90630be8e9851827e9c9209`
- `Linux >= aac23bf636593cc2d67144aed373a46a1a5f76b1 < 5ad981249be52f5e4e92e0e97b436b569071cb86`
- `Linux >= aac23bf636593cc2d67144aed373a46a1a5f76b1 < c65bd945d1c08c3db756821b6bf9f1c4a77b29c6`
- `Linux 3.14`

## Remediation

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