CVE-2026-28231 json
pillow_heif Has Integer Overflow in Encode Path Buffer Validation that Leads to Heap Out-of-Bounds Read
published 2026-02-27 8 mo ago modified 2026-07-20 3 mo ago also GHSA-5gjj-6r7v-ph3x , PYSEC-2026-2248 , PYSEC-2026-2258 , EUVD-2026-9061
- cvss
- 9.1
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.7%
- EPSS 0.7% chance of exploitation in 30 days, percentile 53%
- public exploits
- 0
- none known
Summary
pillow_heif is a Python library for working with HEIF images and plugin for Pillow. Prior to version 1.3.0, an integer overflow in the encode path buffer validation of `_pillow_heif.c` allows an attacker to bypass bounds checks by providing large image dimensions, resulting in a heap out-of-bounds read. This can lead to information disclosure (server heap memory leaking into encoded images) or denial of service (process crash). No special configuration is required — this triggers under default settings. Version 1.3.0 fixes the issue.
Patch / fix
- pypi pi-heif 1.3.0
- pypi pillow-heif 1.3.0
- bigcat88 pillow-heif 1.3.0
- python-pillow-heif openSUSE Tumbleweed 1.3.0-1.1
opensuse advisories openSUSE-SU-2026:10285-1
CISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 8 mo ago
Exploit prediction
0.70% chance of exploitation in the next 30 days, higher than 53% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- github.com https://github.com/bigcat88/pillow_heif/security/advisories/GHSA-5gjj-6r7v-ph3x referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 5.5 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P |
| CNA | 4.0 | 5.5 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P/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 |
| NVD | 3.1 | 9.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H |
| OSV | 3.1 | 9.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| pypi | pi-heif | <1.3.0 |
1.3.0 |
| pypi | pillow-heif | <1.3.0 |
1.3.0 |
Affected products
- bigcat88 pillow_heif
Classification
References
-
github.com
/bigcat88/pillow_heif/commit/8305a15d3780c533b762578cbe987d27a2c59c7a
web, patch
-
github.com
/bigcat88/pillow_heif/security/advisories/GHSA-5gjj-6r7v-ph3x
web, exploit, mitigation, vendor-advisory, evidence
-
github.com
/bigcat88/pillow_heif/releases/tag/v1.3.0
web, product, release-notes, advisory
-
nvd.nist.gov
/vuln/detail/CVE-2026-28231
advisory
-
github.com
/bigcat88/pillow_heif
package
-
github.com
/pypa/advisory-database/tree/main/vulns/pi-heif/PYSEC-2026-2248.yaml
web
-
github.com
/pypa/advisory-database/tree/main/vulns/pillow-heif/PYSEC-2026-2258.yaml
web
Sources
- CVE List CVE-2026-28231
- GitHub Advisory GHSA-5gjj-6r7v-ph3x
- NVD CVE-2026-28231
- OSV PYSEC-2026-2248
- OSV PYSEC-2026-2258
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.