CVE-2018-13305 — In FFmpeg 4

In FFmpeg 4.0.1, due to a missing check for negative values of the mquant variable, the vc1_put_blocks_clamped function in libavcodec/vc1_block.c may trigger an out-of-array access while converting a crafted AVI file to MPEG4, leading to an information disclosure or a denial of s

01What is this vulnerability?

In FFmpeg 4.0.1, due to a missing check for negative values of the mquant variable, the vc1_put_blocks_clamped function in libavcodec/vc1_block.c may trigger an out-of-array access while converting a crafted AVI file to MPEG4, leading to an information disclosure or a denial of service.

02Affected products

Vendor	Product	Versions
n	a / n/a	n/a

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

• Patch to a fixed version listed in the vendor advisory (see references below).
• Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
• Hunt historical logs for exploitation indicators — see Detection signatures below.

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Ask SARA in chat to draft a starting detection for this CVE in your stack of choice.

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

• Published: 2018-07-05T17:00:00.000Z
• Last modified: 2024-08-05T09:00:35.134Z

09References

• github.com — https://github.com/FFmpeg/FFmpeg/commit/d08d4a8c7387e758d439b0592782e4cfa2b4d6a4
• lists.opensuse.org — http://lists.opensuse.org/opensuse-security-announce/2020-01/msg00012.html