CVE-2021-33815

dwa_uncompress in libavcodec/exr.c in FFmpeg 4.4 allows an out-of-bounds array access because...

8.8 HighFix available

dwa_uncompress in libavcodec/exr.c in FFmpeg 4.4 allows an out-of-bounds array access because dc_count is not strictly checked.

Attack profile

How easy it is to exploit

Attack vector: Network
Complexity: Low
Privileges needed: None
User interaction: Required

What an attacker can affect

Confidentiality: High
Integrity: High
Availability: High

Exploit likelihood

1.36%Up 0.9 points since Jun 4, 2021

What each source reports

NVD Score used 8.8

dwa_uncompress in libavcodec/exr.c in FFmpeg 4.4 allows an out-of-bounds array access because dc_count is not strictly checked.

Record: CVE-2021-33815
CVSS 3.1: 8.8 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CVSS 2.0: 6.8 MediumAV:N/AC:M/Au:N/C:P/I:P/A:P
Weakness: CWE-129
Updated: 2026-11-02

CVE List No score

dwa_uncompress in libavcodec/exr.c in FFmpeg 4.4 allows an out-of-bounds array access because dc_count is not strictly checked.

Record: CVE-2021-33815
Updated: 2026-11-02

EUVDEUVD-2021-20491 No score

dwa_uncompress in libavcodec/exr.c in FFmpeg 4.4 allows an out-of-bounds array access because dc_count is not strictly checked.

Record: EUVD-2021-20491
Updated: 2026-11-03

GitHub AdvisoriesGHSA-gcpj-pp7m-cw8v 8.8

dwa_uncompress in libavcodec/exr.c in FFmpeg 4.4 allows an out-of-bounds array access because...

dwa_uncompress in libavcodec/exr.c in FFmpeg 4.4 allows an out-of-bounds array access because dc_count is not strictly checked.

Record: GHSA-gcpj-pp7m-cw8v
CVSS 3.1: 8.8 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Weakness: CWE-129
Updated: 2026-11-02

OSVALPINE-CVE-2021-33815 8.8

dwa_uncompress in libavcodec/exr.c in FFmpeg 4.4 allows an out-of-bounds array access because dc_count is not strictly checked.

Record: ALPINE-CVE-2021-33815
CVSS 3.1: 8.8 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Updated: 2026-11-03

OSV 8.8

dwa_uncompress in libavcodec/exr.c in FFmpeg 4.4 allows an out-of-bounds array access because dc_count is not strictly checked.

Record: CVE-2021-33815
CVSS 3.1: 8.8 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Updated: 2026-11-07

OSVJLSEC-2025-114 8.8

`dwa_uncompress` in `libavcodec/exr.c` in FFmpeg 4.4 allows an out-of-bounds array access because...

dwa_uncompress in libavcodec/exr.c in FFmpeg 4.4 allows an out-of-bounds array access because dc_count is not strictly checked.

Record: JLSEC-2025-114
CVSS 3.1: 8.8 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CVSS 2.0: 6.8 MediumAV:N/AC:M/Au:N/C:P/I:P/A:P
Updated: 2026-11-02

OSVUBUNTU-CVE-2021-33815 8.8

dwa_uncompress in libavcodec/exr.c in FFmpeg 4.4 allows an out-of-bounds array access because dc_count is not strictly checked.

Record: UBUNTU-CVE-2021-33815
CVSS 3.1: 8.8 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Updated: 2026-11-02

OSVopenSUSE-SU-2024:10754-1 No score

ffmpeg-4-4.4-5.2 on GA media

These are all security issues fixed in the ffmpeg-4-4.4-5.2 package on the GA media of openSUSE Tumbleweed.

Record: openSUSE-SU-2024:10754-1
Updated: 2026-11-02

Affected products

ffmpeg

Affected packages

Affected packages
Package	Affected	Fixed
`ffmpeg` Alpine:v3.14	before 4.4-r1	4.4-r1
`ffmpeg` Alpine:v3.15	before 4.4-r1	4.4-r1
`ffmpeg` Alpine:v3.16	before 4.4-r1	4.4-r1
`ffmpeg` Alpine:v3.17	before 4.4-r1	4.4-r1
`ffmpeg` Alpine:v3.18	before 4.4-r1	4.4-r1
`ffmpeg` Alpine:v3.19	before 4.4-r1	4.4-r1
`ffmpeg` Alpine:v3.20	before 4.4-r1	4.4-r1
`ffmpeg` Alpine:v3.21	before 4.4-r1	4.4-r1
`ffmpeg` Alpine:v3.22	before 4.4-r1	4.4-r1
`ffmpeg` Alpine:v3.23	before 4.4-r1	4.4-r1

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Affected packages
Package	Affected	Fixed
`ffmpeg` Alpine:v3.24	before 4.4-r1	4.4-r1
`ffmpeg4` Alpine:v3.16	before 4.4-r1	4.4-r1
`ffmpeg4` Alpine:v3.17	before 4.4-r1	4.4-r1
`ffmpeg4` Alpine:v3.18	before 4.4-r1	4.4-r1
`ffmpeg4` Alpine:v3.19	before 4.4-r1	4.4-r1
`ffmpeg4` Alpine:v3.20	before 4.4-r1	4.4-r1
`ffmpeg4` Alpine:v3.21	before 4.4-r1	4.4-r1
`ffmpeg4` Alpine:v3.22	before 4.4-r1	4.4-r1
`FFMPEG_jll` Julia	4.4.0+0 up to 4.4.2+0	4.4.2+0
`ffmpeg-4` openSUSE:Tumbleweed From an advisory covering 46 CVEs	before 4.4-5.2	4.4-5.2

History

History
Recorded	Changed	Sources
Nov 6, 2026	affected, facts
Nov 3, 2026	affected, aliases, references	OSV
Nov 3, 2026	affected
Nov 3, 2026	aliases	EUVD
Nov 2, 2026	first indexed	CVE List, GitHub Advisories, NVD, OSV

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2021-33815 is a high vulnerability (CVSS 8.8) in Ffmpeg, published June 3, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.36%, the 71st percentile. Fixed in ffmpeg 4.4-r1.

References

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