CVE-2021-21848

Name	CVE-2021-21848
Description	An exploitable integer overflow vulnerability exists within the MPEG-4 decoding functionality of the GPAC Project on Advanced Content library v1.0.1. The library will actually reuse the parser for atoms with the “stsz” FOURCC code when parsing atoms that use the “stz2” FOURCC code and can cause an integer overflow due to unchecked arithmetic resulting in a heap-based buffer overflow that causes memory corruption. An attacker can convince a user to open a video to trigger this vulnerability.
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	DSA-4966-1

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
gpac (PTS)	buster	0.5.2-426-gc5ad4e4+dfsg5-5	fixed
	bullseye	1.0.1+dfsg1-4+deb11u1	fixed
	bullseye (security)	1.0.1+dfsg1-4+deb11u2	fixed
	sid	2.0.0+dfsg1-4	fixed

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

Package	Type	Release	Fixed Version	Origin
gpac	source	stretch	(not affected)
gpac	source	buster	(not affected)
gpac	source	bullseye	1.0.1+dfsg1-4+deb11u1	DSA-4966-1
gpac	source	(unstable)	1.0.1+dfsg1-5

Notes

[buster] - gpac <not-affected> (Vulnerable code not present)
[stretch] - gpac <not-affected> (Vulnerable code not present)
https://talosintelligence.com/vulnerability_reports/TALOS-2021-1297
https://github.com/gpac/gpac/commit/b515fd04f5f00f4a99df741042f1efb31ad56351
https://github.com/gpac/gpac/issues/1814