#VU33774 Input validation error in FFmpeg - CVE-2017-14056

Vulnerability identifier: #VU33774

Vulnerability risk: Medium

CVSSv4.0: 4.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2017-14056

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: No

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

Vendor: ffmpeg.sourceforge.net

Description

The vulnerability allows a remote non-authenticated attacker to perform a denial of service (DoS) attack.

In libavformat/rl2.c in FFmpeg 3.3.3, a DoS in rl2_read_header() due to lack of an EOF (End of File) check might cause huge CPU and memory consumption. When a crafted RL2 file, which claims a large "frame_count" field in the header but does not contain sufficient backing data, is provided, the loops (for offset and size tables) would consume huge CPU and memory resources, since there is no EOF check inside these loops.

Mitigation
Install update from vendor's website.

Vulnerable software versions

FFmpeg: 0.29

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External links
https://www.debian.org/security/2017/dsa-3996
https://www.securityfocus.com/bid/100628
https://github.com/FFmpeg/FFmpeg/commit/96f24d1bee7fe7bac08e2b7c74db1a046c9dc0de
https://lists.debian.org/debian-lts-announce/2019/01/msg00006.html

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

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