Medium (6.5). EPSS 1.4% chance of exploitation in the next 30 days.
A denial of service in the subtitle decoder in FFmpeg 3.2 and 4.1 allows attackers to hog the CPU via a crafted video file in Matroska format, because handle_open_brace in libavcodec/htmlsubtitles.c has a complex format argument to sscanf.
Severity
CVSS 3.1
6.5 medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
EPSS
1.4% chance of exploitation in the next 30 days; higher than 73% of CVEs (scores of 2026-10-31)