CVE-2021-32919 Auth bypass in n/a

What is CVE-2021-32919?

CVE-2021-32919 is a high-severity authentication bypass vulnerability in Debian Debian Linux, published on 13 May 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 Prosody before 0.11.9. The undocumented dialback_without_dialback option in mod_dialback enables an experimental feature for server-to-server authentication. It does not correctly authenticate remote server certificates, allowing a remote server to impersonate another server (when this option is enabled).

Weakness: CWE-295

Which versions are affected by CVE-2021-32919?

It affects 3 products.

Products include Debian Debian Linux, Fedoraproject Fedora, Prosody Prosody.

How do I fix CVE-2021-32919?

Upgrade to a fixed version.

Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.

Is CVE-2021-32919 being exploited?

There is no known exploitation of CVE-2021-32919 in the wild and no public exploit code.

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• CVE-2025-39682 Linux Kernel Improper Check for Unusual or Exceptional Conditions Exploited Critical 9.8
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All Debian Debian Linux vulnerabilities

Sources

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

Also known as DEBIAN-CVE-2021-32919, GHSA-c9xv-56cc-gjw2, UBUNTU-CVE-2021-32919.