CVE-2026-46168 mptcp: fix scheduling with atomic in timestamp sockopt

What is CVE-2026-46168?

CVE-2026-46168 is a medium-severity denial of service 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: fix scheduling with atomic in timestamp sockopt

Using lock_sock_fast() (atomic context) around sock_set_timestamp() and sock_set_timestamping() is unsafe, as both helpers can sleep.

Replace lock_sock_fast() with sleepable lock_sock()/release_sock() to avoid scheduling while atomic panic.

Which versions are affected by CVE-2026-46168?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2026-46168?

Apply the vendor's patch.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2026-46168 being exploited?

There is no known exploitation of CVE-2026-46168 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-88998, BELL-CVE-2026-46168, DEBIAN-CVE-2026-46168, GHSA-78r5-m85f-q5m9, ROOT-OS-DEBIAN-12-CVE-2026-46168, ROOT-OS-UBUNTU-2204-CVE-2026-46168 and 2 more.