---
cve: "CVE-2026-113786"
severity: "LOW"
cvss: 2.3
epss: ""
vendor: "py-pdf"
kev: false
exploited: false
published: "2026-10-21 15:17:16"
tags: [cve, security, low]
source: tsecurity.de CVE-Dossier
exported: "2026-10-25T19:10:12+01:00"
---

# CVE-2026-113786

> 2.3 LOW · 🧪 PoC

## Beschreibung

pypdf is a free and open-source pure-python PDF library. Prior to 6.21.1, an attacker can craft a PDF containing image data labeled with the /DCTDecode filter that causes Pillow to select and invoke an unintended image parser when the image is loaded. Environments without the optional Pillow dependency are not affected. This issue is fixed in version 6.21.1.

## CNA-Record (Kanon, cvelistV5)

- CNA: **GitHub_M**
- State: PUBLISHED
- Stand: 2026-10-21 14:38:39
- CNA-CVSS: **2.3** (`CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N`)

## CVSS-Vektor

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

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

## Schwachstellen-Klasse

- **CWE-183** — Permissive List of Allowed Inputs
  The product implements a protection mechanism that relies on a list of inputs (or properties of inputs) that are explicitly allowed by policy because the inputs are assumed to be safe, but the list is too permissive - that is, it allows an input that is unsafe, leading to resultant weaknesses.
- **CWE-20** — Improper Input Validation
  The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.

## Angriffsmuster (CAPEC)

- [CAPEC-3 — Using Leading 'Ghost' Character Sequences to Bypass Input Filters](https://capec.mitre.org/data/definitions/3.html) _(Severity: Medium)_
- [CAPEC-43 — Exploiting Multiple Input Interpretation Layers](https://capec.mitre.org/data/definitions/43.html) _(Severity: High)_
- [CAPEC-71 — Using Unicode Encoding to Bypass Validation Logic](https://capec.mitre.org/data/definitions/71.html) _(Severity: High)_
- [CAPEC-120 — Double Encoding](https://capec.mitre.org/data/definitions/120.html) _(Severity: Medium)_

## Patch verfügbar (OSV)

- 1a6de8d43c3a931b1ab3643c8dee2c9b51a32d42 (Commit)
- 512d8eb94eb04be1d1c90504e6da2dcef8679e07 (Commit)

## Referenzen

- <https://github.com/py-pdf/pypdf/security/advisories/GHSA-5hx5-vpf9-5wcv>
- <https://github.com/py-pdf/pypdf/pull/4222>
- <https://github.com/py-pdf/pypdf/commit/512d8eb94eb04be1d1c90504e6da2dcef8679e07>
- <https://github.com/py-pdf/pypdf/releases/tag/6.21.1>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/sicherheitsluecken/cve-2026-113786/) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI WID (CSAF)_