CVE-2021-21843 Integer overflow in GPAC

What is CVE-2021-21843?

CVE-2021-21843 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 arithmetic resulting in a heap-based buffer overflow that causes memory corruption. After validating the number of ranges, at [41] the library will multiply the count by the size of the GF_SubsegmentRangeInfo structure. On a 32-bit platform, this multiplication can result in an integer overflow causing the space of the array being allocated to be less than expected. 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-2021-21843?

It affects 2 products.

Products include Debian Debian Linux, Gpac Gpac.

How do I fix CVE-2021-21843?

Upgrade to a fixed version.

Is CVE-2021-21843 being exploited?

There is no known exploitation of CVE-2021-21843 in the wild and no public exploit code.

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• CVE-2024-9680 Mozilla Firefox Use-After-Free Exploited Critical 9.8

All Debian Debian Linux vulnerabilities

Sources

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

Also known as DEBIAN-CVE-2021-21843, GHSA-pw64-2jph-ghqf, UBUNTU-CVE-2021-21843.