---
cve: "CVE-2025-66019"
severity: "MEDIUM"
cvss: 6.6
epss: "0.4%"
vendor: "py-pdf"
kev: false
exploited: false
published: "2025-11-26 00:15:51"
tags: [cve, security, medium]
source: tsecurity.de CVE-Dossier
exported: "2026-09-24T23:42:37+02:00"
---

# CVE-2025-66019

> 6.6 MEDIUM · 🧪 PoC

## Beschreibung

pypdf is a free and open-source pure-python PDF library. Prior to version 6.4.0, an attacker who uses this vulnerability can craft a PDF which leads to a memory usage of up to 1 GB per stream. This requires parsing the content stream of a page using the LZWDecode filter. This issue has been patched in version 6.4.0.

## CVSS-Vektor

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

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

## Patch verfügbar (OSV)

- 96186725e5e6f237129a58a97cd19204a9ce40b2 (Commit)
- 310e571f2be1bc406a20b738e870d1b556d3c3a5 (Commit)

## Referenzen

- <https://github.com/py-pdf/pypdf/security/advisories/GHSA-m449-cwjh-6pw7>
- <https://github.com/py-pdf/pypdf/commit/96186725e5e6f237129a58a97cd19204a9ce40b2>
- <https://github.com/py-pdf/pypdf/releases/tag/6.4.0>
- <https://aydinnyunus.github.io/2025/12/20/cve-2025-66019-pypdf-lzw-dos/>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2025-66019) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_