CVE-2026-31536 smb: server: let send_done handle a completion without IB_SEND_SIGNALED

What is CVE-2026-31536?

CVE-2026-31536 is a critical vulnerability in Linux kernel, published on 24 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

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

smb: server: let send_done handle a completion without IB_SEND_SIGNALED

With smbdirect_send_batch processing we likely have requests without IB_SEND_SIGNALED, which will be destroyed in the final request that has IB_SEND_SIGNALED set.

If the connection is broken all requests are signaled even without explicit IB_SEND_SIGNALED.

Which versions are affected by CVE-2026-31536?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2026-31536?

Apply the vendor's patch.

Is CVE-2026-31536 being exploited?

There is no known exploitation of CVE-2026-31536 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 BELL-CVE-2026-31536, DEBIAN-CVE-2026-31536, GHSA-pgx3-cx3f-6g2v, ROOT-OS-DEBIAN-12-CVE-2026-31536, ROOT-OS-DEBIAN-13-CVE-2026-31536, ROOT-OS-UBUNTU-2204-CVE-2026-31536 and 2 more.