CVE-2026-75146 PUBLISHED

FFmpeg Out-of-Bounds Read in DASH Demuxer via dashdec.c

Assigner: VulnCheck
Reserved: 17.08.2026 Published: 19.08.2026 Updated: 19.08.2026

FFmpeg before commit 65b0dab contains an out-of-bounds read in the DASH demuxer (libavformat/dashdec.c). When a live DASH manifest is refreshed with a startNumber that is lower than the previous value, the current sequence number is driven negative. The fragment retrieval function checked only the upper bound before indexing the fragments array, allowing a negative index to be used and causing an out-of-bounds read. A malicious or misconfigured DASH server can trigger this by serving a live manifest with a decreasing startNumber across a manifest refresh.

Metrics

CVSS Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:N/VA:H/SC:N/SI:N/SA:N
CVSS Score: 7.2

Product Status

Vendor FFmpeg
Product FFmpeg
Versions Default: unaffected
  • affected from 0 to 65b0dab903e5975e036b30ecc58f5935d4f151e0 (excl.)

Credits

  • Joshua Rogers (AISLE Research) finder

References

Problem Types

  • Out-of-bounds Read CWE