CVE-2026-107660

FFmpeg before 8.1.3 and 9.x before 9.0.2 contains an improper certificate validation vulnerability in tls_open() of libavformat/tls_mbedtls.c, which skips hostname checks for IP-address hosts. Network attackers can intercept https, rtmps, or tls connections to IP-literal URLs with any trusted CA-issued certificate to read and tamper with streams.

Score

CVSS 4.0 6.3 Medium

Status

Analyzed - disclosure@vulncheck.com

Published

2026-10-08

Last modified

2026-10-14

Weaknesses

CWE-297

Affected products

• Ffmpeg (Ffmpeg)

References

• https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/24383
• https://code.ffmpeg.org/FFmpeg/FFmpeg/commit/57a2e704b4a6eda5d061b45aacde6b19c026bfc0
• https://code.ffmpeg.org/FFmpeg/FFmpeg/commit/d377212904a19fc740d721cbda0ba58fa3805a29
• https://code.ffmpeg.org/FFmpeg/FFmpeg/commit/0cd2a70eacd510c2efed48b9fc177c7cb2bc549f
• https://github.com/FFmpeg/FFmpeg/blob/n9.0.1/libavformat/tls_mbedtls.c#L676-L681
• https://ffmpeg.org/
• https://www.vulncheck.com/advisories/ffmpeg-before-8.1.3-and-9-x-before-9.0.2-mbedtls-hostname-verification-bypass-for-…