CVE-2026-98573

Updated on 18 Oct 2026

Severity

7.0 High severity

Details

CVSS score
7.0

Overview

About vulnerability

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

net: skbuff: fix pull-bound underflow in skb_checksum_setup_ipv6()

skb_maybe_pull_tail() subtracts skb_headlen(skb) from the unsigned max argument and passes the result to __pskb_pull_tail() as a signed int. The function does not ensure that max is at least skb_headlen(skb).

This can happen while parsing IPv6 extension headers when an skb already has a linear area larger than MAX_IPV6_HDR_LEN. Once the parser needs data beyond the linear area, max - skb_headlen(skb) wraps and is converted to a negative delta. __pskb_pull_tail() then passes that negative length to skb_copy_bits(), where it can become a very large copy length.

Pass the requested length itself as the pull bound at the three extension-header call sites, so the delta can no longer go negative.

Details

Fixes

KernelCare state

Live-patch status from KernelCare for each operating system.

Operating system Status Covered kernels
Debian 12 Released
44 kernels
  • 6.1.38-1
  • 6.1.38-2
  • 6.1.38-4
  • 6.1.52-1
  • 6.1.55-1
  • 6.1.64-1
  • 6.1.66-1
  • 6.1.69-1
  • 6.1.76-1
  • 6.1.27-1
  • 6.1.67-1
  • 6.1.85-1
  • 6.1.90-1
  • 6.1.94-1
  • 6.1.99-1
  • 6.1.106-3
  • 6.1.112-1
  • 6.1.115-1
  • 6.1.119-1
  • 6.1.123-1
  • 6.1.128-1
  • 6.1.124-1
  • 6.1.129-1
  • 6.1.133-1
  • 6.1.135-1
  • 6.1.137-1
  • 6.1.140-1
  • 6.1.139-1
  • 6.1.147-1
  • 6.1.148-1
  • 6.1.153-1
  • 6.1.158-1
  • 6.1.159-1
  • 6.1.162-1
  • 6.1.164-1
  • 6.1.170-1
  • 6.1.170-3
  • 6.1.172-1
  • 6.1.174-1
  • 6.1.170-2
  • 6.1.176-1
  • 6.1.177-1
  • 6.1.180-1
  • 6.1.187-1
Oracle Linux 8 UEK 7 Planned —
Oracle Linux 9 UEK 7 Planned —
Ubuntu 22.04 Planned —
Ubuntu 22.04 AWS Planned —
Ubuntu 22.04 Azure Planned —
Ubuntu 26.04 Planned —