CVE-2026-64834: FFmpeg 0.6.3 - 8.1.2 Infinite Loop DoS via RTP/ASF Demuxer

Is it exploited?

Not on CISA's list. CISA has not added it to the Known Exploited Vulnerabilities catalog as of 29 Oct 2026. If CISA adds it, this page shows it as known exploited.

How likely is exploitation in the next 30 days?

0.7%

EPSS score, percentile 54.1 of all scored records. A probability estimated by FIRST, not a report of exploitation.

How severe?

8.7 High

CVSS v4.0 base score, given by the CNA

What should I do?

CISA has set no required action, because the vulnerability is not in KEV.

Advisories and patches (1)

Which versions are affected?

Affected

• 0.6.3 through 8.1.2

Versions by product

Source: CISA KEV 2026.10.29, as of 29 Oct 2026; FIRST EPSS, as of 29 Oct 2026; CVE List, as of 29 Oct 2026. About the data.

What to do

Advisories and patches

• Patch Commit (Patch)

This summary is based on the CVE record as of 29 Oct 2026. Check the vendor's advisory before you act: affected versions and fixes can change.

Affected products and versions

As listed in the CVE record.

Versions not listed are: affected.

Source: CVE List, as of 29 Oct 2026. About the data.

About this vulnerability

FFmpeg versions 0.6.3 through 8.1.2 contain an infinite loop vulnerability in the RTP/ASF demuxer within libavformat/rtpdec_asf.c that allows remote attackers to cause denial of service by sending a crafted RTP/ASF stream. The rtp_asf_fix_header function fails to validate a minimum chunksize when iterating over ASF objects, causing the loop pointer to never advance when a chunksize is smaller tha…

Summary: CVE record, as of 29 Oct 2026.

• CISA has not added CVE-2026-64834 to its Known Exploited Vulnerabilities (KEV) catalog, as of 29 Oct 2026.
• The CVE record was published on 22 Jul 2026.
• The CVE record carries a CVSS v4.0 base score of 8.7 (High), given by its CNA.
• FIRST's EPSS model puts the probability of exploitation in the next 30 days at 0.7% (percentile 54.1), as of 29 Oct 2026. EPSS is a statistical estimate, not a report of exploitation.
• CISA's SSVC assessment in the CVE record: exploitation none, automatable yes, technical impact partial.
• The credits in the CVE record name AISLE as finder.

Source: CISA KEV 2026.10.29, as of 29 Oct 2026; CVE List, as of 29 Oct 2026; FIRST EPSS, as of 29 Oct 2026. About the data.

Description

FFmpeg 0.6.3 - 8.1.2 Infinite Loop DoS via RTP/ASF Demuxer

FFmpeg versions 0.6.3 through 8.1.2 contain an infinite loop vulnerability in the RTP/ASF demuxer within libavformat/rtpdec_asf.c that allows remote attackers to cause denial of service by sending a crafted RTP/ASF stream. The rtp_asf_fix_header function fails to validate a minimum chunksize when iterating over ASF objects, causing the loop pointer to never advance when a chunksize is smaller than the 24-byte minimum ASF object header size, resulting in CPU exhaustion that denies service to legitimate users.

Source: CVE List, as of 29 Oct 2026. About the data.

Timeline