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CVE-2026-64834 (GCVE-0-2026-64834)

Vulnerability from cvelistv5 – Published: 2026-07-22 17:06 – Updated: 2026-07-28 01:06 X_Open Source
VLAI
Title
FFmpeg 0.6.3 - 8.1.2 Infinite Loop DoS via RTP/ASF Demuxer
Summary
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.
Severity
8.7 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-23 15:50 UTC
CWE
  • CWE-835 - Loop with Unreachable Exit Condition ('Infinite Loop')
Assigner
References
Impacted products
Vendor Product Version CPE status
FFmpeg FFmpeg Affected: 0.6.3 , ≤ 8.1.2 (semver)
Affected: 11d5f475be95d22d5f0692220cc772b116abc632 (git)
    cpe:2.3:a:ffmpeg:ffmpeg:*:*:*:*:*:*:*:*
    cpe:2.3:a:ffmpeg:ffmpeg:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-07-02 00:00
Credits
Pavel Kohout, Aisle Research
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.


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