CVE-2025-39834 net/mlx5: HWS, Fix memory leak in hws_action_get_shared_stc_nic error flow

What is CVE-2025-39834?

CVE-2025-39834 is a medium-severity denial of service vulnerability in Linux kernel, published on 16 Sep 2025. 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:

net/mlx5: HWS, Fix memory leak in hws_action_get_shared_stc_nic error flow

When an invalid stc_type is provided, the function allocates memory for shared_stc but jumps to unlock_and_out without freeing it, causing a memory leak.

Fix by jumping to free_shared_stc label instead to ensure proper cleanup.

Weakness: CWE-401

Which versions are affected by CVE-2025-39834?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2025-39834?

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-2025-39834 being exploited?

There is no known exploitation of CVE-2025-39834 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-2025-39834, DEBIAN-CVE-2025-39834, GHSA-45vc-784v-vp78, ROOT-OS-DEBIAN-13-CVE-2025-39834, UBUNTU-CVE-2025-39834.