CVE-2021-21855 Integer overflow in GPAC

What is CVE-2021-21855?

CVE-2021-21855 is a high-severity vulnerability in Debian Debian Linux, published on 18 Aug 2021. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

Official description

Multiple exploitable integer overflow vulnerabilities exist within the MPEG-4 decoding functionality of the GPAC Project on Advanced Content library v1.0.1. A specially crafted MPEG-4 input can cause an integer overflow due to unchecked addition 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.

Weakness: CWE-119, CWE-680

Which versions are affected by CVE-2021-21855?

It affects 2 products.

Products include Debian Debian Linux, Gpac Gpac.

How do I fix CVE-2021-21855?

Upgrade to a fixed version.

Is CVE-2021-21855 being exploited?

There is no known exploitation of CVE-2021-21855 in the wild and no public exploit code.

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All Debian Debian Linux vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as DEBIAN-CVE-2021-21855, GHSA-9h3c-xp73-7mv7, UBUNTU-CVE-2021-21855.