CVE-2021-3999

Name	CVE-2021-3999
Description	A flaw was found in glibc. An off-by-one buffer overflow and underflow in getcwd() may lead to memory corruption when the size of the buffer is exactly 1. A local attacker who can control the input buffer and size passed to getcwd() in a setuid program could use this flaw to potentially execute arbitrary code and escalate their privileges on the system.
Source	CVE (at NVD; CERT, LWN, oss-sec, fulldisc, bugtraq, EDB, Metasploit, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, Mageia, GitHub advisories/code/issues, web search, more)
References	DLA-3152-1

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
glibc (PTS)	buster	2.28-10+deb10u1	vulnerable
	buster (security)	2.28-10+deb10u2	fixed
	bullseye	2.31-13+deb11u5	fixed
	bookworm, sid	2.36-8	fixed

The information below is based on the following data on fixed versions.

Package	Type	Release	Fixed Version	Origin
glibc	source	buster	2.28-10+deb10u2	DLA-3152-1
glibc	source	bullseye	2.31-13+deb11u4
glibc	source	(unstable)	2.33-4

Notes

https://sourceware.org/bugzilla/show_bug.cgi?id=28769
https://www.openwall.com/lists/oss-security/2022/01/24/4
https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=23e0e8f5f1fb5ed150253d986ecccdc90c2dcd5e
https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=472e799a5f2102bc0c3206dbd5a801765fceb39c