CVE-2026-46158 mptcp: pm: ADD_ADDR rtx: always decrease sk refcount

What is CVE-2026-46158?

CVE-2026-46158 is a medium-severity memory corruption vulnerability in Linux kernel, published on 28 May 2026. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

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

mptcp: pm: ADD_ADDR rtx: always decrease sk refcount

When an ADD_ADDR is retransmitted, the sk is held in sk_reset_timer(). It should then be released in all cases at the end.

Some (unlikely) checks were returning directly instead of calling sock_put() to decrease the refcount. Jump to a new 'exit' label to call __sock_put() (which will become sock_put() in the next commit) to fix this potential leak.

While at it, drop the '!msk' check which cannot happen because it is never reset, and explicitly mark the remaining one as "unlikely".

Which versions are affected by CVE-2026-46158?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2026-46158?

Apply the vendor's patch.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2026-46158 being exploited?

There is no known exploitation of CVE-2026-46158 in the wild and no public exploit code.

Other vulnerabilities in Linux kernel

• CVE-2026-53266 Linux Kernel Out-of-Bounds Write Exploited High 8.8
• CVE-2013-6282 Linux Kernel Improper Input Validation Exploited High 8.8
• CVE-2022-0185 Linux Kernel Heap-Based Buffer Overflow Exploited High 8.4
• CVE-2013-2094 Linux Kernel Privilege Escalation Exploited High 8.4
• CVE-2026-53362 Linux Kernel Unspecified Exploited High 7.8

All Linux kernel vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as AZL-88824, BELL-CVE-2026-46158, DEBIAN-CVE-2026-46158, GHSA-vj5h-6xr8-8f8g, ROOT-OS-DEBIAN-11-CVE-2026-46158, ROOT-OS-DEBIAN-12-CVE-2026-46158 and 4 more.