---
id: CVE-2026-98555
title: 'llc: fix skb UAF and leaks on llc_mac_hdr_init() failure'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  llc: fix skb UAF and leaks on llc_mac_hdr_init() failure

  In llc_conn_ac_resend_i_xxx_x_set_0_or_send_rr(), if llc_mac_hdr_init()
  fails, kfree_skb(skb) is called instea…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <
    fec0fe6838a7f45175667701fb51abb23a6ffb1e
  - >-
    Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <
    b859ba18b5a1067f71db5618c6a4a70d55fa308b
  - >-
    Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <
    8b855b645841b5a04e20339a22bb6d593c9b790d
  - >-
    Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <
    d360b31f1a3666579422872aa7d1a751e20b76f9
  - >-
    Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <
    060f827aa3dc47939ee306da715cd6700d129616
  - >-
    Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <
    41dcae82bece9f106b4dff0ee777bba8d157c8a8
  - >-
    Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <
    cb3528ad8bb46fa6252f5d14ced7febddc18515d
  - >-
    Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <
    72f9dd522f8d6c5a00be9695c7bb74631eb5069e
  - Linux 2.6.12
published: '2026-10-18'
updated: '2026-10-18'
sourceUpdated: '2026-10-18T15:18:22.631Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-98555'
references:
  - url: 'https://git.kernel.org/stable/c/fec0fe6838a7f45175667701fb51abb23a6ffb1e'
  - url: 'https://git.kernel.org/stable/c/b859ba18b5a1067f71db5618c6a4a70d55fa308b'
  - url: 'https://git.kernel.org/stable/c/8b855b645841b5a04e20339a22bb6d593c9b790d'
  - url: 'https://git.kernel.org/stable/c/d360b31f1a3666579422872aa7d1a751e20b76f9'
  - url: 'https://git.kernel.org/stable/c/060f827aa3dc47939ee306da715cd6700d129616'
  - url: 'https://git.kernel.org/stable/c/41dcae82bece9f106b4dff0ee777bba8d157c8a8'
  - url: 'https://git.kernel.org/stable/c/cb3528ad8bb46fa6252f5d14ced7febddc18515d'
  - url: 'https://git.kernel.org/stable/c/72f9dd522f8d6c5a00be9695c7bb74631eb5069e'
tags:
  - cve.org
ingestedAt: '2026-10-18T15:45:12.263Z'
---

## Overview

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

llc: fix skb UAF and leaks on llc_mac_hdr_init() failure

In llc_conn_ac_resend_i_xxx_x_set_0_or_send_rr(), if llc_mac_hdr_init()
fails, kfree_skb(skb) is called instead of kfree_skb(nskb). This leaks
the newly allocated nskb, reads from the freed skb via LLC_I_GET_NR(pdu),
and double-frees skb when llc_conn_state_process() drops its reference.

In llc_sap_action_send_xid_r() and llc_sap_action_send_test_r(), nskb is
leaked if llc_mac_hdr_init() returns an error.

Free nskb in all three error paths.

## Affected

- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < fec0fe6838a7f45175667701fb51abb23a6ffb1e`
- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < b859ba18b5a1067f71db5618c6a4a70d55fa308b`
- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 8b855b645841b5a04e20339a22bb6d593c9b790d`
- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < d360b31f1a3666579422872aa7d1a751e20b76f9`
- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 060f827aa3dc47939ee306da715cd6700d129616`
- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 41dcae82bece9f106b4dff0ee777bba8d157c8a8`
- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < cb3528ad8bb46fa6252f5d14ced7febddc18515d`
- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 72f9dd522f8d6c5a00be9695c7bb74631eb5069e`
- `Linux 2.6.12`

## Remediation

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