---
cve: "CVE-2026-96640"
severity: "HIGH"
cvss: 8.2
epss: "0.5%"
vendor: "python-pillow"
kev: false
exploited: false
published: "2026-10-21 21:20:32"
tags: [cve, security, high]
source: tsecurity.de CVE-Dossier
exported: "2026-10-30T18:01:38+01:00"
---

# CVE-2026-96640

> 8.2 HIGH · 🧪 PoC

## Beschreibung

Pillow is a Python imaging library. From 5.1.0 until 13.0.0, PdfParser.linearize_page_tree() in src/PIL/PdfParser.py treats a PDF /Pages graph as a tree without tracking duplicate indirect references. When Image.save(..., format="PDF", append=True) processes an attacker-controlled existing PDF whose /Kids arrays repeatedly reference the same child /Pages node, Pillow expands the shared subtree as distinct pages. A compact malformed PDF can therefore create exponentially many page references and consume disproportionate CPU before the append completes. This issue is fixed in version 13.0.0.

## CNA-Record (Kanon, cvelistV5)

- CNA: **GitHub_M**
- State: PUBLISHED
- Stand: 2026-10-28 01:57:01
- CNA-CVSS: **8.2** (`CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N`)

## CISA-Anreicherung (vulnrichment/ADP)

- CISA-SSVC (Coordinator, v2.0.3):
  - Exploitation: **poc**
  - Automatable: **yes**
  - Technical Impact: **partial**

## CVSS-Vektor

```
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Netzwerk | bad |
| AC Komplexität | Gering | bad |
| PR Privilegien | Keine | bad |
| UI Interaktion | Keine | bad |

## Schwachstellen-Klasse

- **CWE-400** — Uncontrolled Resource Consumption
  The product does not properly control the allocation and maintenance of a limited resource.
- **CWE-407** — Inefficient Algorithmic Complexity
  An algorithm in a product has an inefficient worst-case computational complexity that may be detrimental to system performance and can be triggered by an attacker, typically using crafted manipulations that ensure that the worst case is being reached.

## Angriffsmuster (CAPEC)

- [CAPEC-147 — XML Ping of the Death](https://capec.mitre.org/data/definitions/147.html) _(Severity: Medium)_
- [CAPEC-227 — Sustained Client Engagement](https://capec.mitre.org/data/definitions/227.html)
- [CAPEC-492 — Regular Expression Exponential Blowup](https://capec.mitre.org/data/definitions/492.html)

## ATT&CK-Techniken

- [T1499 — Endpoint Denial of Service](https://attack.mitre.org/techniques/T1499/)

## Patch verfügbar (OSV)

- 293218ad059d994baf1777d882911bed6a49704a (Commit)
- 6f0e7ee1f9c2fe227906f8a4b926e6622b702bc7 (Commit)

## Referenzen

- <https://github.com/python-pillow/Pillow/security/advisories/GHSA-mrfp-p49p-3hf2>
- <https://github.com/python-pillow/Pillow/pull/10093>
- <https://github.com/python-pillow/Pillow/commit/6f0e7ee1f9c2fe227906f8a4b926e6622b702bc7>
- <https://github.com/python-pillow/Pillow/releases/tag/13.0.0>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/sicherheitsluecken/cve-2026-96640/) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI WID (CSAF)_