Out-of-bounds write in Linux kernel - CVE-2026-89783
Published: September 17, 2026
Vulnerability identifier: #VU150509
CSH Severity: High
CVSS v4: 9.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-89783
CWE-ID: CWE-787
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to compromise confidentiality, integrity, and availability.
The vulnerability exists due to an out-of-bounds write in xfrm6_input_addr() when processing an inner IPv6 packet containing a destination-options HAO option or a type-2 routing header. A remote attacker can send a specially crafted packet to compromise confidentiality, integrity, and availability.
Exploitation requires the transport-mode receive path to re-enter IPv6 input with a secpath whose length is at the maximum depth.
Affected software
Linux kernel
How to mitigate CVE-2026-89783
Install security update from vendor's repository.
External References
- https://git.kernel.org/stable/c/0f679e0523ddfff3fb554336ceb874b0e51e9cd3
- https://git.kernel.org/stable/c/48996649222e95008cdb98cd58579e3fc8e5ee06
- https://git.kernel.org/stable/c/5d9e3bf34fec9a5d237e4b7cef4a707bc2e091bc
- https://git.kernel.org/stable/c/5f35a29a5eed3d80befd32050843ac88dea3d61a
- https://git.kernel.org/stable/c/68e8737fe8e72f085c608cff322b3d2de8340af1
- https://git.kernel.org/stable/c/8fe2c53fb81f5ad5be43af2ad09583f7c78b4b77
- https://git.kernel.org/stable/c/91fc387f63c00ddfb5221127a17bac97549a8343
- https://git.kernel.org/stable/c/bdcda866c89f9a8b1acdabf02d26cde9fbe501d8