#VU92207 Unchecked Return Value in FFmpeg - CVE-2021-38114

Vulnerability identifier: #VU92207

Vulnerability risk: Low

CVSSv4.0: 1.7 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-38114

CWE-ID: CWE-252

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
FFmpeg
Universal components / Libraries / Libraries used by multiple products

Vendor: ffmpeg.sourceforge.net

Description

The vulnerability allows a local user to perform a denial of service (DoS) attack.

The vulnerability exists due to libavcodec/dnxhddec.c in FFmpeg does not check the return value of the init_vlc function. A local user can trick the victim into opening a specially crafted file to trigger resource exhaustion and perform a denial of service (DoS) attack.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

FFmpeg: 4.4

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External links
https://github.com/FFmpeg/FFmpeg/commit/7150f9575671f898382c370acae35f9087a30ba1
https://patchwork.ffmpeg.org/project/ffmpeg/patch/PAXP193MB12624C21AE412BE95BA4D4A4B6F09@PAXP193MB1262.EURP193.PROD.OUTLOOK.COM/
https://lists.debian.org/debian-lts-announce/2021/08/msg00018.html
https://www.debian.org/security/2021/dsa-4990
https://www.debian.org/security/2021/dsa-4998

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Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.