CVE-2024-44940 fou: remove warn in gue_gro_receive on unsupported protocol

What is CVE-2024-44940?

CVE-2024-44940 is a high-severity denial of service vulnerability in Debian Debian Linux, published on 26 Aug 2024. 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:

fou: remove warn in gue_gro_receive on unsupported protocol

Drop the WARN_ON_ONCE inn gue_gro_receive if the encapsulated type is not known or does not have a GRO handler.

Such a packet is easily constructed. Syzbot generates them and sets off this warning.

Remove the warning as it is expected and not actionable.

The warning was previously reduced from WARN_ON to WARN_ON_ONCE in commit 270136613bf7 ("fou: Do WARN_ON_ONCE in gue_gro_receive for bad proto callbacks").

Which versions are affected by CVE-2024-44940?

It affects 2 products.

Products include Debian Debian Linux, Linux kernel.

How do I fix CVE-2024-44940?

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-2024-44940 being exploited?

There is no known exploitation of CVE-2024-44940 in the wild and no public exploit code.

Other vulnerabilities in Debian Debian Linux

• CVE-2015-3306 ProFTPD Improper Access Control Exploited Critical 10.0
• CVE-2025-49113 RoundCube Webmail Deserialization of Untrusted Data Exploited Critical 9.9
• CVE-2026-24061 GNU InetUtils Argument Injection Exploited Critical 9.8
• CVE-2025-39682 Linux Kernel Improper Check for Unusual or Exceptional Conditions Exploited Critical 9.8
• CVE-2024-9680 Mozilla Firefox Use-After-Free Exploited Critical 9.8

All Debian Debian Linux vulnerabilities

Sources

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

Also known as AZL-49140, BELL-CVE-2024-44940, DEBIAN-CVE-2024-44940, GHSA-3mqr-vvf3-23jj, UBUNTU-CVE-2024-44940.