CVE-2021-32558 Denial of service in n/a

What is CVE-2021-32558?

CVE-2021-32558 is a high-severity denial of service vulnerability in Debian Debian Linux, published on 27 Jul 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

An issue was discovered in Sangoma Asterisk 13.x before 13.38.3, 16.x before 16.19.1, 17.x before 17.9.4, and 18.x before 18.5.1, and Certified Asterisk before 16.8-cert10. If the IAX2 channel driver receives a packet that contains an unsupported media format, a crash can occur.

Weakness: CWE-74

Which versions are affected by CVE-2021-32558?

It affects 3 products.

Products include Debian Debian Linux, Digium Asterisk, Digium Certified Asterisk.

How do I fix CVE-2021-32558?

Upgrade to a fixed version.

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-2021-32558 being exploited?

There is no known exploitation of CVE-2021-32558 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 ALPINE-CVE-2021-32558, DEBIAN-CVE-2021-32558, DLA-2729-1, GHSA-xhjf-mf8w-q63p, UBUNTU-CVE-2021-32558.