CVE-2021-3156: Sudo Heap-Based Buffer Overflow Vulnerability

CVE-2021-3156 · Severity: critical · CVSS 7.8 · Exploited in the wild · Published 2022-04-06

Sudo contains an off-by-one error leading to a heap-based buffer overflow. An attacker can achieve root privilege escalation by using 'sudoedit -s' with a command-line argument ending in a single backslash.

Technologies: Sudo. Vendors: Sudo.

Quick answers

Is CVE-2021-3156 exploited in the wild?
Yes. CVE-2021-3156 is known to be exploited in the wild, first recorded on 6 April 2022. Treat it as urgent.
How severe is CVE-2021-3156?
Critical severity, with a CVSS score of 7.8, published 6 April 2022.
Which products and versions are affected?
Sudo Project Sudo before 1.9.5p2.
Is there a fix for CVE-2021-3156?
No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2021-3156 attacked?
It is attacked with local access, in an operating system.
Am I affected by CVE-2021-3156?
Check whether you run Sudo. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Affected products

  • Sudo Project Sudo before 1.9.5p2

Timeline

  • 2021-01-26: disclosed: Initial public disclosure via Openwall and other sources.
  • 2022-04-06: kev added: Added to CISA Known Exploited Vulnerabilities Catalog.
  • 2022-04-06: other: Published date listed in advisory.

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