CVE-2026-32882libheif: Heap Buffer OOB Read in overlay compositing due to wrong alpha stride
- 7.1HighCVSS base score
- 0.71%Exploitation in 30 daysEPSS · top 46% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- YesPublic exploitsa reference or SSVC says so
Description
libheif is a HEIF and AVIF file format decoder and encoder. Versions 1.21.2 and prior contain a heap buffer over-read in HeifPixelImage::overlay() in libheif/pixelimage.cc. When compositing an overlay image (iovl) whose child image has a different bit depth for the alpha channel than for the color channels, the function indexes into the alpha plane using the color channel stride (in_stride) instead of the previously retrieved alpha_stride, causing reads past the end of the alpha buffer (up to 3,123 bytes for a 100×50 image with 10-bit color and 8-bit alpha). A crafted HEIF file can exploit this to cause a denial of service (crash) or potentially disclose adjacent heap memory through leaked bytes embedded in the decoded output pixels. This issue has been fixed in versionThis issue has been fixed in version 1.22.0.
Public exploit
An exploit or proof of concept is public: anyone can try it against an unpatched system. A reference of the record is tagged as an exploit. CISA's SSVC rates its exploitation: a proof of concept is public.
Show the exploits1
References tagged exploit1 reference
- https://github.com/strukturag/libheif/security/advisories/GHSA-hg7q-rjr2-8x46 (opens in a new tab)x_refsource_CONFIRMexploit
Timeline
ID reserved
By GitHub_M
- 2 months later
· 2 months later
Published
- 57 days later
· 57 days later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | High7.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:H |
| redhat-SADPADP (enrichment) | 3.1 | High7.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:H |
| NVDNVD · Deferred | 3.1 | High7.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:H |
- EPSS (exploitation in 30 days)
- 0.71% · top 46% of all CVEs (13 Nov 2026)
- CISA SSVC
- Exploitation: poc · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.1.
Affected products
- affected < 1.22.0
References
References5
- https://github.com/strukturag/libheif/security/advisories/GHSA-hg7q-rjr2-8x46 (opens in a new tab)x_refsource_CONFIRMexploit
- https://github.com/strukturag/libheif/releases/tag/v1.22.0 (opens in a new tab)x_refsource_MISC
- https://access.redhat.com/security/cve/CVE-2026-32882 (opens in a new tab)vdb-entryx_refsource_REDHAT
- RHBZ#2480000 (opens in a new tab)issue-trackingx_refsource_REDHAT
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-32882.json (opens in a new tab)x_sadp-csaf-vex
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-30981 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-32882)Record last updated .