CVE-2026-66040
FFmpeg Heap Out-of-Bounds Write via PNG/APNG eXIf Encoder
FFmpeg through 8.1.2, fixed in commit b506faf, contains a heap out-of-bounds write vulnerability in the native PNG and APNG encoders that allows remote attackers to corrupt heap memory by supplying a crafted PNG image with a malicious eXIf chunk. Attackers can craft an eXIf chunk where multiple IFD entries reference the same large value payload, causing canonical serialization to expand the output far beyond the undersized allocation estimated by add_exif_profile_size(), resulting in png_write_chunk() writing tens of thousands of bytes past the buffer boundary, leading to deterministic heap corruption, process crash, and potentially arbitrary code execution.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Passive
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
8.7
FFmpeg Heap Out-of-Bounds Write via PNG/APNG eXIf Encoder
FFmpeg through 8.1.2, fixed in commit b506faf, contains a heap out-of-bounds write vulnerability in the native PNG and APNG encoders that allows remote attackers to corrupt heap memory by supplying a crafted PNG image with a malicious eXIf chunk. Attackers can craft an eXIf chunk where multiple IFD entries reference the same large value payload, causing canonical serialization to expand the output far beyond the undersized allocation estimated by add_exif_profile_size(), resulting in png_write_chunk() writing tens of thousands of bytes past the buffer boundary, leading to deterministic heap corruption, process crash, and potentially arbitrary code execution.
- Record
CVE-2026-66040- CVSS 4.0
- 8.7 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-122
- Updated
- 2026-11-02
EUVDEUVD-2026-48742
8.7
FFmpeg through 8.1.2, fixed in commit b506faf, contains a heap out-of-bounds write vulnerability in the native PNG and APNG encoders that allows remote attackers to corrupt heap memory by supplying a crafted PNG image with a malicious eXIf chunk. Attackers can craft an eXIf chunk where multiple IFD entries reference the same large value payload, causing canonical serialization to expand the output far beyond the undersized allocation estimated by add_exif_profile_size(), resulting in png_write_chunk() writing tens of thousands of bytes past the buffer boundary, leading to deterministic heap corruption, process crash, and potentially arbitrary code execution.
- Record
EUVD-2026-48742- CVSS 4.0
- 8.7 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-6vcg-882j-82v5
8.7
FFmpeg through 8.1.2, fixed in commit b506faf, contains a heap out-of-bounds write vulnerability...
FFmpeg through 8.1.2, fixed in commit b506faf, contains a heap out-of-bounds write vulnerability in the native PNG and APNG encoders that allows remote attackers to corrupt heap memory by supplying a crafted PNG image with a malicious eXIf chunk. Attackers can craft an eXIf chunk where multiple IFD entries reference the same large value payload, causing canonical serialization to expand the output far beyond the undersized allocation estimated by add_exif_profile_size(), resulting in png_write_chunk() writing tens of thousands of bytes past the buffer boundary, leading to deterministic heap corruption, process crash, and potentially arbitrary code execution.
- Record
GHSA-6vcg-882j-82v5- CVSS 4.0
- 8.7 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-122
- Updated
- 2026-11-02
NVD
8.7
FFmpeg through 8.1.2, fixed in commit b506faf, contains a heap out-of-bounds write vulnerability in the native PNG and APNG encoders that allows remote attackers to corrupt heap memory by supplying a crafted PNG image with a malicious eXIf chunk. Attackers can craft an eXIf chunk where multiple IFD entries reference the same large value payload, causing canonical serialization to expand the output far beyond the undersized allocation estimated by add_exif_profile_size(), resulting in png_write_chunk() writing tens of thousands of bytes past the buffer boundary, leading to deterministic heap corruption, process crash, and potentially arbitrary code execution.
- Record
CVE-2026-66040- CVSS 4.0
- 8.7 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-122
- Updated
- 2026-11-02
OSV
8.7
FFmpeg Heap Out-of-Bounds Write via PNG/APNG eXIf Encoder
FFmpeg through 8.1.2, fixed in commit b506faf, contains a heap out-of-bounds write vulnerability in the native PNG and APNG encoders that allows remote attackers to corrupt heap memory by supplying a crafted PNG image with a malicious eXIf chunk. Attackers can craft an eXIf chunk where multiple IFD entries reference the same large value payload, causing canonical serialization to expand the output far beyond the undersized allocation estimated by add_exif_profile_size(), resulting in png_write_chunk() writing tens of thousands of bytes past the buffer boundary, leading to deterministic heap corruption, process crash, and potentially arbitrary code execution.
- Record
CVE-2026-66040- CVSS 4.0
- 8.7 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - Weakness
- CWE-122
- Updated
- 2026-11-02
OSVDEBIAN-CVE-2026-66040
8.8
FFmpeg through 8.1.2, fixed in commit b506faf, contains a heap out-of-bounds write vulnerability in the native PNG and APNG encoders that allows remote attackers to corrupt heap memory by supplying a crafted PNG image with a malicious eXIf chunk. Attackers can craft an eXIf chunk where multiple IFD entries reference the same large value payload, causing canonical serialization to expand the output far beyond the undersized allocation estimated by add_exif_profile_size(), resulting in png_write_chunk() writing tens of thousands of bytes past the buffer boundary, leading to deterministic heap corruption, process crash, and potentially arbitrary code execution.
- Record
DEBIAN-CVE-2026-66040- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVJLSEC-2026-1186
8.7
FFmpeg through 8.1.2, fixed in commit b506faf, contains a heap out-of-bounds write vulnerability...
FFmpeg through 8.1.2, fixed in commit b506faf, contains a heap out-of-bounds write vulnerability in the native PNG and APNG encoders that allows remote attackers to corrupt heap memory by supplying a crafted PNG image with a malicious eXIf chunk. Attackers can craft an eXIf chunk where multiple IFD entries reference the same large value payload, causing canonical serialization to expand the output far beyond the undersized allocation estimated by add_exif_profile_size(), resulting in png_write_chunk() writing tens of thousands of bytes past the buffer boundary, leading to deterministic heap corruption, process crash, and potentially arbitrary code execution.
- Record
JLSEC-2026-1186- CVSS 4.0
- 8.7 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVUBUNTU-CVE-2026-66040
8.7
FFmpeg through 8.1.2, fixed in commit b506faf, contains a heap out-of-bounds write vulnerability in the native PNG and APNG encoders that allows remote attackers to corrupt heap memory by supplying a crafted PNG image with a malicious eXIf chunk. Attackers can craft an eXIf chunk where multiple IFD entries reference the same large value payload, causing canonical serialization to expand the output far beyond the undersized allocation estimated by add_exif_profile_size(), resulting in png_write_chunk() writing tens of thousands of bytes past the buffer boundary, leading to deterministic heap corruption, process crash, and potentially arbitrary code execution.
- Record
UBUNTU-CVE-2026-66040- CVSS 4.0
- 8.7 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
ffmpegDebian:12 |
All versions, plus listed versions 7:5.1.3-17:5.1.3-27:5.1.4-0+deb12u17:5.1.5-0+deb12u17:5.1.6-0+deb12u1 Show 45 moreShow less7:5.1.7-0+deb12u17:5.1.8-0+deb12u17:5.1.9-0+deb12u17:6.0-17:6.0-27:6.0-37:6.0-47:6.0-57:6.0-67:6.0-77:6.0-87:6.0-97:6.1-17:6.1-27:6.1-37:6.1-47:6.1-57:6.1.1-17:6.1.1-27:6.1.1-37:6.1.1-47:6.1.1-57:7.0-17:7.0.1-17:7.0.1-27:7.0.1-37:7.0.1-47:7.0.1-57:7.0.2-17:7.0.2-27:7.0.2-37:7.1-17:7.1-27:7.1-37:7.1-47:7.1.1-17:7.1.2-17:7.1.3-17:8.0-17:8.0-27:8.0.1-17:8.0.1-27:8.0.1-37:8.1-17:8.1-2 |
None known |
ffmpegDebian:13 |
All versions, plus listed versions 7:7.1.1-17:7.1.2-0+deb13u17:7.1.2-17:7.1.3-0+deb13u17:7.1.3-1 Show 19 moreShow less7:7.1.4-0+deb13u17:7.1.5-0+deb13u17:8.0-17:8.0-27:8.0.1-17:8.0.1-27:8.0.1-37:8.1-17:8.1-27:8.1-37:8.1.1-17:8.1.1-27:8.1.1-37:8.1.1-47:8.1.2-17:8.1.2-27:9.0-17:9.0.1-17:9.0.2-1 |
None known |
ffmpegDebian:14 |
before 7:9.0.2-1, plus listed versions 7:7.1.1-17:7.1.2-17:7.1.3-17:8.0-17:8.0-2 Show 14 moreShow less7:8.0.1-17:8.0.1-27:8.0.1-37:8.1-17:8.1-27:8.1-37:8.1.1-17:8.1.1-27:8.1.1-37:8.1.1-47:8.1.2-17:8.1.2-27:9.0-17:9.0.1-1 |
7:9.0.2-1 |
FFMPEG_jllJulia |
before 9.0.0+0 | 9.0.0+0 |
FFMPEG_nogpl_jllJulia |
before 9.0.0+0 | 9.0.0+0 |
FFplay_jllJulia |
before 9.0.0+0 | 9.0.0+0 |
libavUbuntu:Pro:14.04:LTS |
All versions, plus listed versions 6:0.8.7-1ubuntu26:9.10-1ubuntu16:9.10-1ubuntu26:9.10-1ubuntu56:9.10-1ubuntu6 Show 9 moreShow less6:9.10-1ubuntu76:9.11-2ubuntu16:9.11-2ubuntu26:9.13-0ubuntu0.14.04.16:9.14-0ubuntu0.14.04.16:9.16-0ubuntu0.14.04.16:9.18-0ubuntu0.14.04.16:9.20-0ubuntu0.14.04.16:9.20-0ubuntu0.14.04.1+esm1 |
None known |
ffmpegUbuntu:26.10 |
All versions, plus listed versions 7:8.0.1-3ubuntu27:8.1-3ubuntu37:8.1.2-2ubuntu2 |
None known |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-66040 is a high vulnerability (CVSS 8.7) in Ffmpeg, published July 24, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.78%, the 55th percentile. Fixed in ffmpeg 7:9.0.2-1.
References
code.ffmpeg.org/FFmpeg/FFmpeg/pulls/23786
code.ffmpeg.org/FFmpeg/FFmpeg/commit/b506fafec9a19fcbc2be5271875fd4a63d6615bc
vulncheck.com/advisories/ffmpeg-heap-out-of-bounds-write-via-png-apng-exif-encoder
nvd.nist.gov/vuln/detail/CVE-2026-66040
github.com/advisories/GHSA-6vcg-882j-82v5
code.ffmpeg.org/FFmpeg/FFmpeg
Left out here: 10 versions. The JSON record has them.