CVE-2021-3772 Denial of service in kernel

What is CVE-2021-3772?

CVE-2021-3772 is a medium-severity denial of service vulnerability in Debian Debian Linux, published on 2 Mar 2022. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

A flaw was found in the Linux SCTP stack. A blind attacker may be able to kill an existing SCTP association through invalid chunks if the attacker knows the IP-addresses and port numbers being used and the attacker can send packets with spoofed IP addresses.

Weakness: CWE-354

Which versions are affected by CVE-2021-3772?

It affects 18 products.

Products include Debian Debian Linux, Linux kernel, Netapp E-Series Santricity Os Controller, Netapp H300s Firmware, Netapp H410c Firmware, Netapp H410s Firmware and 12 more.

How do I fix CVE-2021-3772?

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-2021-3772 being exploited?

There is no known exploitation of CVE-2021-3772 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 DEBIAN-CVE-2021-3772, GHSA-g6gr-2x73-gj6f, UBUNTU-CVE-2021-3772.