CVE-2016-4422 Auth bypass in n/a

What is CVE-2016-4422?

CVE-2016-4422 is a critical authentication bypass vulnerability in Debian Debian Linux, published on 6 May 2016. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

The pam_sm_authenticate function in pam_sshauth.c in libpam-sshauth might allow context-dependent attackers to bypass authentication or gain privileges via a system user account.

Weakness: CWE-287

Which versions are affected by CVE-2016-4422?

It affects 2 products.

Products include Debian Debian Linux, Libpam-Sshauth Project Libpam-Sshauth.

How do I fix CVE-2016-4422?

Apply the vendor's patch.

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

Is CVE-2016-4422 being exploited?

There is no known exploitation of CVE-2016-4422 in the wild and no public exploit code.

Other vulnerabilities in Debian Debian Linux

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• 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 DSA-3567-1, GHSA-c337-rr2j-g4h6, UBUNTU-CVE-2016-4422.