CVE-2026-112396: Pillow: Heap use-after-free when encoding TIFF to an in-memory buffer
Vulnerability summary
CVE-2026-112396 is a high (CVSS 7.5) Use After Free vulnerability in python-pillow pillow. EPSS estimates a 0.69% chance of exploitation in the next 30 days, higher than 52.9% of scored vulnerabilities. 1 public exploit is recorded.
Not severe (CVSS 5.9, network access); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 1 · Related 1Timeline
- 19-10-2026PublishedVulnerability first disclosed.
- 20-10-2026Last modifiedVulnerability information updated.
Description
Pillow is a Python imaging library. From 11.3.0 until 13.0.0, Pillow has a heap use-after-free when libtiff rejects a tag while encoding TIFF data to an in-memory buffer. When an application saves attacker-influenced TIFF tags to BytesIO, libtiff can reject a tag during encoding in ImagingLibTiffEncode; the error path then frees the output buffer without closing or clearing the TIFF handle, and later cleanup flushes through the write callback into freed memory, which can crash the process and may enable code execution. This issue is fixed in version 13.0.0.
CVSS metrics
7 scores · 7 sources · 1 version- CVE.orgCNA5.9MediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:HDiffers
- OSV · PypiEcosystem advisory · calculated7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- OSV · WolfiEcosystem advisory · calculated5.9MediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:HDiffers
- OSV · ChainguardEcosystem advisory · calculated5.9MediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:HDiffers
- OSV · DebianEcosystem advisory · calculated7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- OSV · UbuntuEcosystem advisory · calculated7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS trend
Probability
0.69%
Chance of exploitation in the next 30 days
Percentile
53%
Versus all other CVEs
30-day change
Change unavailable
Change unavailable
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
1 foundPillow
Maturity: poc
Weaknesses
CWE · root causeAffected systems
Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.
Chainguard25 products
- apache-beam-python-3.12-sdkAll versions (No fix recorded) | < 2.77.0-r5
- mlflowAll versions (No fix recorded) | < 3.17.2-r2
- mlflow-fipsAll versions (No fix recorded) | < 3.17.2-r3
- nemo-gymAll versions (No fix recorded) | < 0.5.0_rc0_git20260729-r6
- nemo-rl-cuda-13.0All versions (No fix recorded) | < 0.7.0-r11
Wolfi6 products
- mlflowAll versions (No fix recorded)
- open-webuiAll versions (No fix recorded) | < 0.12.3-r6
- py3.10-pillowAll versions (No fix recorded)
- py3.11-pillowAll versions (No fix recorded) | < 13.0.0-r0
- py3.12-pillowAll versions (No fix recorded) | < 13.0.0-r0
Ubuntu2 products
- pillowAll versions (No fix recorded)
- pillow-python2All versions (No fix recorded)
Debian1 product
- pillowAll versions (No fix recorded)
PyPI1 product
- pillow≥ 11.3.0, < 13.0.0
Python1 product
- pillow≥ 11.3.0, < 13.0.0
Python-pillow1 product
- pillow≥ 11.3.0, < 13.0.0
7 vendors · 37 products
References
9 links- github.com/python-pillow/Pillow/security/advisories/GHSA-4rr5-89j8-mwwmX Refsource CONFIRMWEBAdvisoryREPORTExploitVendor AdvisoryEVIDENCE
- github.com/python-pillow/Pillow/commit/dc95da20207827a062cfbf551ee9f6031465a8bbX Refsource MISCWEBFIXPatch
