Out-of-bounds read in Linux kernel - CVE-2026-64551

Vulnerability details

The vulnerability allows a local user to disclose uninitialized memory.

The vulnerability exists due to an out-of-bounds read in sctp_sf_do_5_2_6_stale() when processing an ERROR chunk with a STALE_COOKIE cause in the COOKIE_ECHOED state. A local user can send a specially crafted SCTP packet to disclose uninitialized memory.

The leaked value is echoed to the peer in the Cookie Preservative of the reply INIT. Exploitation is reachable by a peer that can drive an association into COOKIE_ECHOED, including an unprivileged process using a raw SCTP socket in a user and network namespace.

Affected software

How to mitigate CVE-2026-64551

External References

• https://git.kernel.org/stable/c/08a8f2d13f703924316e9aeac863a88ef50990c7
• https://git.kernel.org/stable/c/1cd23ca80784223fa2204e16203f754da4e821f8
• https://git.kernel.org/stable/c/588706ebaf8cdb4a4161602949eba365514b1db1
• https://git.kernel.org/stable/c/6022da37786701df1fc5dd946a6dcba59d5473b1
• https://git.kernel.org/stable/c/861f884f5471632c731cbbd612a1c072e391a624
• https://git.kernel.org/stable/c/a257b41ddfe9e327b26581ad2777f04b23ac73f5
• https://git.kernel.org/stable/c/bbd6b2ea966cf57b6ae095cf5a8dbc993cd197a0
• https://git.kernel.org/stable/c/ebe0a55d954fa8da383b6192edb8f763dcb002d5

Related Security Bulletins

• Out-of-bounds read in Linux kernel sctp
• Debian update for linux