CVE-2026-58049 — Security Box Score

CVE · referencelatest edition

Reference page — cumulative record through Wednesday, August 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.

CVE-2026-58049HIGH

FFmpeg - Out-of-Bounds Write in RASC Decoder decode_dlta()

  AV  AC  AT  PR  UI  VC  VI  VA   CVSS    EPSS   %ile   KEV
   N   L   N   N   N   L   L   H    8.8   .0027   20.0     —

AFFECTED
  Product  Versions     Fixed
  FFmpeg   unspecified  —

TIMELINE
  Jun 28  Reserved by VulnCheck
  Jun 28  Published (CNA: VulnCheck)
  Jul 21  EXPLOIT PUBLISHED — CVE-2026-58049 (FFmpeg). Public exploit reference added.
  Aug 18  EXPLOIT PUBLISHED — CVE-2026-58049 (FFmpeg). Public exploit reference added.

CWE-787 · CNA: VulnCheck · CVSS v4.0 · 10 references · NVD status: Awaiting Analysis

Description

FFmpeg's RASC video decoder (decode_dlta in libavcodec/rasc.c) performs 32-bit reads and writes at the row cursor before the NEXT_LINE row-boundary check and validates the DLTA region in pixel rather than byte units, so a DLTA run on a PAL8 frame can access several bytes past the row allocation. A crafted media stream using the RASC FourCC, decoded by libavcodec, triggers a bitstream-controlled out-of-bounds heap write and adjacent out-of-bounds read, leading to memory corruption.

Lifecycle

Complete event history — 4 events, chronological
Date	Event	Detail
June 28, 2026	Reserved	Reserved by VulnCheck
June 28, 2026	Published	Published (CNA: VulnCheck)
July 21, 2026	EXPLOIT PUBLISHED	EXPLOIT PUBLISHED — CVE-2026-58049 (FFmpeg). Public exploit reference added.
August 18, 2026	EXPLOIT PUBLISHED	EXPLOIT PUBLISHED — CVE-2026-58049 (FFmpeg). Public exploit reference added.

Affected

Affected products and packages — 1 row
Vendor	Product / Package	Ecosystem	Version introduced	Fixed
FFmpeg	FFmpeg	—	—	—

Weaknesses

CWE-787

References (10)

https://access.redhat.com/errata/RHSA-2026:43711 [vendor-advisory, x_refsource_REDHAT]
https://access.redhat.com/errata/RHSA-2026:51180 [vendor-advisory, x_refsource_REDHAT]
https://access.redhat.com/errata/RHSA-2026:52832 [vendor-advisory, x_refsource_REDHAT]
https://access.redhat.com/errata/RHSA-2026:52833 [vendor-advisory, x_refsource_REDHAT]
https://access.redhat.com/security/cve/CVE-2026-58049 [vdb-entry, x_refsource_REDHAT]
https://bugzilla.redhat.com/show_bug.cgi?id=2493952 [issue-tracking, x_refsource_REDHAT]
https://github.com/FFmpeg/FFmpeg/blob/master/libavcodec/rasc.c [product]
https://github.com/bikini/exploitarium/tree/main/ffmpeg-rasc-dlta-calc-poc [exploit, third-party-advisory]
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-58049.json [x_sadp-csaf-vex]
https://www.vulncheck.com/advisories/ffmpeg-out-of-bounds-write-in-rasc-decoder-decode-dlta [third-party-advisory]

Authoritative record: CVE-2026-58049 at cve.org

Vendors: ffmpeg

Weaknesses: CWE-787

About this page

This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-58049 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Wednesday, August 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.