What is CVE-2019-9717?

CVE-2019-9717 is a medium-severity vulnerability in Libav, classified under Uncontrolled Resource Consumption. CVSS score: 6.5/10. Published 2019-09-19.

How severe is CVE-2019-9717?

Medium severity. CVSS v3 base score is 6.5 out of 10.

Resource exhaustion in Libav

CVE-2019-9717

In Libav 12.3, a denial of service in the subtitle decoder allows attackers to hog the CPU via a crafted video file in Matroska format, because srt_to_ass in libavcodec/srtdec.c has a complex format argument to sscanf.

Vulnerability class: DoS (Denial of Service)

Published 2019-09-19 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.013 (68.8th percentile), scored 2026-09-29.

Low probability of exploitation in the next 30 days, but still tracked. 69th percentile — 68.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.013 · newest: 0.013 · change: 0.000

Affected products

Libav

Weakness classification (CWE)

CWE-400 — Uncontrolled Resource Consumption

References

github.com/libav/libav/blob/df744e3cf66548c9167ea857104a29d2ea92819e/libavcodec… (Exploit, Third Party Advisory)
lgtm.com/security/ (Third Party Advisory)

Frequently asked questions

What is CVE-2019-9717?: CVE-2019-9717 is a medium-severity vulnerability in Libav, classified under Uncontrolled Resource Consumption. CVSS score: 6.5/10. Published 2019-09-19.
How severe is CVE-2019-9717?: Medium severity. CVSS v3 base score is 6.5 out of 10.