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.

The remote Ubuntu 18.04 LTS / 20.04 LTS / 22.04 LTS / 24.04 LTS host has packages installed that are affected by multiple vulnerabilities as referenced in the USN-8716-1 advisory.

    It was discovered that FFmpeg incorrectly handled certain crafted media files in the VobSub subtitle     demuxer. An attacker could possibly use this issue to cause a denial of service or execute arbitrary code.
    (CVE-2026-64830)

    It was discovered that FFmpeg incorrectly handled certain crafted DTS audio streams in the S/PDIF muxer.
    An attacker could possibly use this issue to cause a denial of service or expose sensitive information.
    (CVE-2026-64833)

    It was discovered that FFmpeg incorrectly handled certain crafted RTP/ASF streams. An attacker could     possibly use this issue to cause a denial of service. (CVE-2026-64834)

    It was discovered that FFmpeg incorrectly handled certain crafted ADX audio files. This issue only     affected Ubuntu 22.04 LTS and Ubuntu 24.04 LTS. (CVE-2026-64835)

    It was discovered that FFmpeg incorrectly handled certain crafted AVI files in the TDSC video decoder. An     attacker could possibly use this issue to cause a denial of service or execute arbitrary code.
    (CVE-2026-65703)

    It was discovered that FFmpeg incorrectly handled certain crafted ffconcat files processed via the TY     demuxer. This issue only affected Ubuntu 20.04 LTS, Ubuntu 22.04 LTS, and Ubuntu 24.04 LTS.
    (CVE-2026-65704)

    It was discovered that FFmpeg incorrectly handled certain crafted video streams in the vf_floodfill video     filter. This issue only affected Ubuntu 18.04 LTS, Ubuntu 20.04 LTS, Ubuntu 22.04 LTS, and Ubuntu 24.04     LTS. (CVE-2026-65705)

    It was discovered that FFmpeg incorrectly handled certain crafted NV12 video frames in the vf_swaprect     video filter. This issue only affected Ubuntu 18.04 LTS, Ubuntu 20.04 LTS, Ubuntu 22.04 LTS, and Ubuntu     24.04 LTS. (CVE-2026-65706)

    It was discovered that FFmpeg incorrectly handled certain crafted hvcC NAL arrays in the HEVC parser. An     attacker could possibly use this issue to cause a denial of service or execute arbitrary code.
    (CVE-2026-75141)

    It was discovered that FFmpeg incorrectly handled certain crafted MPEG system headers. An attacker could     possibly use this issue to cause a denial of service or execute arbitrary code. (CVE-2026-75142)

    It was discovered that FFmpeg incorrectly handled certain crafted network input in the librist protocol     handler. This issue only affected Ubuntu 22.04 LTS and Ubuntu 24.04 LTS. (CVE-2026-75143)

    It was discovered that FFmpeg incorrectly handled certain crafted Dirac data units in the VC2 HQ RTP     packetizer. An attacker could possibly use this issue to cause a denial of service or execute arbitrary     code. (CVE-2026-75144)

    It was discovered that FFmpeg incorrectly handled certain crafted DASH manifests. This issue only affected     Ubuntu 18.04 LTS, Ubuntu 20.04 LTS, Ubuntu 22.04 LTS, and Ubuntu 24.04 LTS. (CVE-2026-75146)

Tenable has extracted the preceding description block directly from the Ubuntu security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The Unity Linux 20 host has a package installed that is affected by a vulnerability as referenced in the UTSA-2026-104793 advisory.

    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.

Tenable has extracted the preceding description block directly from the Unity Linux security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - 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. (CVE-2026-75146)

Note that Nessus relies on the presence of the package as reported by the vendor.

ID	Name	Product	Family	Type	Severity
344622	Ubuntu 18.04 LTS / 20.04 LTS / 22.04 LTS / 24.04 LTS : FFmpeg vulnerabilities (USN-8716-1)	Nessus	Ubuntu Local Security Checks	Local	critical
340916	Unity Linux 20.1050e / 20.1060e / 20.1070e Security Update: ffmpeg (UTSA-2026-104793)	Nessus	Unity Linux Local Security Checks	Local	high
338206	Linux Distros Unpatched Vulnerability : CVE-2026-75146	Nessus	Misc.	Local	high

Detections

Analytics

CVE-2026-75146

high

Tenable Plugins

critical

high

high