Unbounded memory expansion in Pillow MSP RLE decoder
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- —
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Partial Red Hat: 9 fixed, 9 without a fix
Attack profile from CVSS 4.0 · CNA. Fix status from CNA, GitHub and Red Hat.
Summary
Pillow from 4.1.0 before 13.0.0 is affected. The MSP RLE decoder writes run-length output to an in-memory buffer without limiting expansion to the declared image size (CWE-409). A remote attacker who supplies a crafted MSP image to an application that loads its pixels can exhaust memory and deny service, even when the declared pixel count passes the decompression-bomb check.
Written with Claude Haiku 5.5 from the sources below · 2026-11-07
Description from the CNA
Pillow is a Python imaging library. From 4.1.0 until 13.0.0, Pillow's MSP RLE decoder can expand a small file into an unbounded in-memory buffer. The decoder writes run-length output to BytesIO without limiting expansion to the declared image size. An attacker can supply a crafted MSP image to an application that loads its pixels. This can exhaust memory and deny service even when the declared pixel count passes the decompression-bomb check. This issue is fixed in version 13.0.0.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| python-pillow | Pillow | 4.1.0 to before 13.0.0 | 13.0.0 | Patch available | CNA |
| — | pillow (PyPI) | 4.1.0 to before 13.0.0 | 13.0.0 | Patch available | GHSA-gg2r-wvfm-q9rx |
- Pillow Vendorpython-pillow Affected 4.1.0 to before 13.0.0 Fixed in 13.0.0 Patch available CNA
- pillow (PyPI) Vendor— Affected 4.1.0 to before 13.0.0 Fixed in 13.0.0 Patch available GHSA-gg2r-wvfm-q9rx
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:python:pillow:*:*:*:*:*:*:*:* | 4.1.0 to before 13.0.0 | Vulnerable | python-pillow |
- cpe:2.3:a:python:pillow:*:*:*:*:*:*:*:* Versions 4.1.0 to before 13.0.0 Vulnerable ·python-pillow
Remediation
Fixed in Pillow and PyPI pillow 13.0.0. Red Hat fixes python-pillow in RHSA-2026:92639, Satellite in RHSA-2026:95655, RHSA-2026:95656, RHSA-2026:95657 and RHSA-2026:92861, and AI Inference Server 3.5 and OpenShift AI 3.5 in RHSA-2026:94738, RHSA-2026:94721, RHSA-2026:94717, RHSA-2026:94715, RHSA-2026:94709, RHSA-2026:94702 and RHSA-2026:94631. Red Hat's plan is none available for Ansible Automation Platform 2, RHEL AI 3, Quay 3, Lightspeed Core, OpenShift Lightspeed, Lightspeed Services for OCP and Exploit Intelligence.
Written with Claude Haiku 5.5 from the sources below · 2026-11-07
- Fix · CNA Pillow (python-pillow) Fixed in 13.0.0
- Fix · GHSA-gg2r-wvfm-q9rx pillow (PyPI) Fixed in 13.0.0 Advisory →
Red Hat 12 advisories
- RHSA-2026:95655 Released 2026-11-05 · Red Hat rating CriticalSatellite 6.16 EUS security update
- Red Hat Satellite 6.16 for RHEL 8 openvox-agent-8.32.0-1.el8sat, openvox-server-8.18.0-1.el8sat, python-brotli-1.2.1-1.el8pc +11
- Red Hat Satellite 6.16 for RHEL 9 openvox-agent-8.32.0-1.el9sat, openvox-server-8.18.0-1.el9sat, python-brotli-1.2.1-1.el9pc +11
- RHSA-2026:95657 Released 2026-11-05 · Red Hat rating CriticalSatellite 6.18 security update
- Red Hat Satellite 6.18 for RHEL 9 openvox-agent-8.32.0-1.el9sat, openvox-server-8.18.0-1.el9sat, python3.12-brotli-1.2.1-1.el9pc +4
- RHSA-2026:95656 Released 2026-11-05 · Red Hat rating CriticalSatellite 6.17 security update
- Red Hat Satellite 6.17 for RHEL 9 openvox-agent-8.32.0-1.el9sat, openvox-server-8.18.0-1.el9sat, python-brotli-1.2.1-1.el9pc +9
Show 9 more Red Hat advisories
- RHSA-2026:94738 Released 2026-11-03 · Red Hat rating CriticalRed Hat AI Inference 3.5.3 (CUDA)
- Red Hat AI Inference Server 3.5 registry.redhat.io/rhaii/vllm-cuda-rhel9
- RHSA-2026:94721 Released 2026-11-03 · Red Hat rating CriticalRed Hat AI Inference Tech Preview 3.5.3 (Gaudi)
- Red Hat AI Inference Server 3.5 registry.redhat.io/rhaii/vllm-gaudi-rhel9
- RHSA-2026:94717 Released 2026-11-03 · Red Hat rating CriticalRed Hat AI Inference 3.5.3 (Spyre)
- Red Hat AI Inference Server 3.5 registry.redhat.io/rhaii/vllm-spyre-rhel9
- RHSA-2026:94715 Released 2026-11-03 · Red Hat rating CriticalRed Hat AI Inference Model Optimization Tools 3.5.3 (CUDA)
- Red Hat AI Inference Server 3.5 registry.redhat.io/rhaii/model-opt-cuda-rhel9
- RHSA-2026:94709 Released 2026-11-03 · Red Hat rating CriticalRed Hat AI Inference 3.5.3 (ROCm)
- Red Hat AI Inference Server 3.5 registry.redhat.io/rhaii/vllm-rocm-rhel9
- RHSA-2026:94702 Released 2026-11-03 · Red Hat rating CriticalRed Hat AI Inference 3.5.3 (CPU)
- Red Hat AI Inference Server 3.5 registry.redhat.io/rhaii/vllm-cpu-rhel9
- RHSA-2026:94631 Released 2026-11-03 · Red Hat rating CriticalGuideLLM 3.5.1
- Red Hat OpenShift AI 3.5 registry.redhat.io/rhai/guidellm-rhel9
- RHSA-2026:92639 Released 2026-10-29 · Red Hat rating Importantpython-pillow security update
- Red Hat Enterprise Linux AppStream (v. 8) python-pillow-5.1.1-33.el8_10, python3-pillow-5.1.1-33.el8_10
- Red Hat Enterprise Linux CRB (v. 8) python3-pillow-5.1.1-33.el8_10, python3-pillow-devel-5.1.1-33.el8_10, python3-pillow-doc-5.1.1-33.el8_10 +1
- RHSA-2026:92861 Released 2026-10-29 · Red Hat rating CriticalSatellite 6.19 security update
- Red Hat Satellite 6.19 for RHEL 9 openvox-agent-8.31.1-1.el9sat, openvox-server-8.17.0-1.el9sat, python3.12-brotli-1.2.1-1.el9pc +6
Vendor assessments
Red Hat
Red Hat rating: Important. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Exploit Intelligence | Affected | No fix yet |
| Lightspeed Core | Affected | No fix yet |
| OpenShift Lightspeed | Affected | No fix yet |
| Red Hat AI Inference Server | Affected | No fix yet |
| Red Hat Ansible Automation Platform 2 | Affected | No fix yet |
| Red Hat Enterprise Linux AI (RHEL AI) 3 | Affected | No fix yet |
| Red Hat Lightspeed Services for OCP | Affected | No fix yet |
| Red Hat OpenShift AI (RHOAI) | Affected | No fix yet |
| Red Hat Quay 3 | Affected | No fix yet |
| Red Hat AI Inference Server 3.5 | Fixed | RHSA-2026:94702, RHSA-2026:94709, RHSA-2026:94715, RHSA-2026:94717, RHSA-2026:94721, RHSA-2026:94738 |
| Red Hat Enterprise Linux AppStream (v. 8) | Fixed | RHSA-2026:92639 |
| Red Hat Enterprise Linux CRB (v. 8) | Fixed | RHSA-2026:92639 |
| Red Hat OpenShift AI 3.5 | Fixed | RHSA-2026:94631 |
| Red Hat Satellite 6.16 for RHEL 8 | Fixed | RHSA-2026:95655 |
| Red Hat Satellite 6.16 for RHEL 9 | Fixed | RHSA-2026:95655 |
| Red Hat Satellite 6.17 for RHEL 9 | Fixed | RHSA-2026:95656 |
| Red Hat Satellite 6.18 for RHEL 9 | Fixed | RHSA-2026:95657 |
| Red Hat Satellite 6.19 for RHEL 9 | Fixed | RHSA-2026:92861 |
Not affected: 8 products
- Red Hat AI Inference Server
- Red Hat Ansible Automation Platform 2
- Red Hat OpenShift AI (RHOAI)
- Red Hat Satellite 6.16 for RHEL 8
- Red Hat Satellite 6.16 for RHEL 9
- Red Hat Satellite 6.17 for RHEL 9
- Red Hat Satellite 6.18 for RHEL 9
- Red Hat Satellite 6.19 for RHEL 9
Timeline
- 2026-10-20 Threatist record created from CVE-2026-112892
- 2026-10-21 Priority changed: MEDIUM → LOW
- 2026-10-21 Alias added: GHSA-gg2r-wvfm-q9rx
- 2026-10-21 Fix available: PyPI/[email protected] · GHSA-gg2r-wvfm-q9rx
- 2026-10-21 CVSS score added · GHSA-gg2r-wvfm-q9rx
- 2026-10-21 Weakness changed · GHSA-gg2r-wvfm-q9rx
- 2026-10-21 5 new references · GHSA-gg2r-wvfm-q9rx
- 2026-10-23 CISA SSVC decision points changed
- 2026-10-23 Affected versions changed · Red Hat
- 2026-10-23 CVSS score added · Red Hat
- 2026-10-24 Affected versions changed · Red Hat
- 2026-10-26 Affected versions changed · Red Hat
- 2026-10-27 CVSS score added · NVD
- 2026-10-30 Fix available: RHSA-2026:92639 · Red Hat
- 2026-10-30 Fix available: Red Hat Enterprise Linux AppStream (v. 8), Red Hat Enterprise Linux CRB (v. 8) · Red Hat
- 2026-10-30 Fix available: Red Hat Satellite 6.19 for RHEL 9 · Red Hat
- 2026-10-31 Fix available: RHSA-2026:92861 · Red Hat
- 2026-11-04 Fix available: RHSA-2026:94717 · Red Hat
- 2026-11-04 Fix available: RHSA-2026:94715 · Red Hat
- 2026-11-04 Fix available: RHSA-2026:94709 · Red Hat
- 2026-11-04 Fix available: RHSA-2026:94738 · Red Hat
- 2026-11-04 Fix available: RHSA-2026:94702 · Red Hat
- 2026-11-04 Fix available: RHSA-2026:94631 · Red Hat
- 2026-11-04 Fix available: RHSA-2026:94721 · Red Hat
- 2026-11-04 Fix available: Red Hat AI Inference Server 3.5, Red Hat OpenShift AI 3.5 · Red Hat
- 2026-11-06 Fix available: Red Hat Satellite 6.16 for RHEL 8, Red Hat Satellite 6.16 for RHEL 9, Red Hat Satellite 6.17 for RHEL 9 +1 · Red Hat
- 2026-11-06 Fix available: RHSA-2026:95656 · Red Hat
- 2026-11-06 Fix available: RHSA-2026:95655 · Red Hat
- 2026-11-06 Fix available: RHSA-2026:95657 · Red Hat
- 2026-11-06 Affected versions changed · Red Hat
- 2026-11-07 Affected versions changed · Red Hat
References
Advisory 2
More python-pillow Pillow vulnerabilities
- TI-2026-76627 Out-of-bounds read in Pillow TIFF encoder ColorMap handling CVSS 4.0HIGH 8.8
- TI-2026-76625 Quadratic-time denial of service in Pillow PDF save_all CVSS 4.0HIGH 8.7
- TI-2026-76605 NULL pointer dereference in Pillow's Image.merge function CVSS 4.0HIGH 8.7
- TI-2026-76604 Out-of-bounds read in Pillow TIFF decoding leaks heap memory CVSS 4.0HIGH 8.8
- TI-2026-76602 Double free in Pillow ImagingScaleAffine on allocation failure CVSS 4.0HIGH 8.7
- TI-2026-76600 GIF seek in Pillow keeps rejected size, allowing denial of service CVSS 4.0HIGH 8.7
Sources
- CVE-2026-112892 · CVE Program
- CVE-2026-112892 · NVD
- FIRST EPSS
- GHSA-gg2r-wvfm-q9rx · GitHub Advisory Database · CC BY 4.0
- CVE-2026-112892 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences