Sudo Vulnerability CVE-2021-3156: Root Access Risk | Qualys

Summary: The Qualys Research Team discovered a heap overflow vulnerability in sudo, tracked as CVE-2021-3156, that lets any unprivileged user gain root privileges on a vulnerable host using a default configuration. The flaw was introduced in July 2011 (commit 8255ed69) and affects legacy versions 1.8.2 through 1.8.31p2 and stable versions 1.9.0 through 1.9.5p1, with Qualys verifying full root exploits on Ubuntu 20.04, Debian 10, and Fedora 33.
Bottom line: The bug sat in plain sight for nearly 10 years, and Qualys notes that even the 'nobody' account can exploit it without being a privileged user or on the sudoers list - so any unprivileged foothold on a Unix or Linux host can become root.

Read the original at Qualys Blog ↗

Topics: Vulnerabilities & Patching
Mentions: CVE-2021-3156
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