---
cve: "CVE-2026-110636"
severity: "CRITICAL"
cvss: 9.3
epss: "2.4%"
vendor: "revolunet"
kev: false
exploited: false
published: "2026-10-14 15:17:16"
tags: [cve, security, critical]
source: tsecurity.de CVE-Dossier
exported: "2026-10-26T15:19:10+01:00"
---

# CVE-2026-110636

> 9.3 CRITICAL · 🧪 PoC

## Beschreibung

pypdftk through 0.5 contains an OS command injection vulnerability in fill_form(), dump_data_fields(), and pdftk_cmd_util() that builds shell commands from caller-supplied paths. Attackers controlling pdf_path or out_file can inject shell metacharacters interpreted by subprocess.Popen with shell=True to execute OS commands as the Python process.

## CNA-Record (Kanon, cvelistV5)

- CNA: **VulnCheck**
- State: PUBLISHED
- Stand: 2026-10-20 01:21:31
- CNA-CVSS: **9.3** (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`)

## CISA-Anreicherung (vulnrichment/ADP)

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

## CVSS-Vektor

```
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/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-78** — Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
  The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component.

## Angriffsmuster (CAPEC)

- [CAPEC-6 — Argument Injection](https://capec.mitre.org/data/definitions/6.html) _(Severity: High)_
- [CAPEC-15 — Command Delimiters](https://capec.mitre.org/data/definitions/15.html) _(Severity: High)_
- [CAPEC-43 — Exploiting Multiple Input Interpretation Layers](https://capec.mitre.org/data/definitions/43.html) _(Severity: High)_
- [CAPEC-88 — OS Command Injection](https://capec.mitre.org/data/definitions/88.html) _(Severity: High)_
- [CAPEC-108 — Command Line Execution through SQL Injection](https://capec.mitre.org/data/definitions/108.html) _(Severity: Very High)_

## Referenzen

- <https://github.com/revolunet/pypdftk/issues/56>
- <https://github.com/revolunet/pypdftk/pull/57>
- <https://github.com/revolunet/pypdftk/blob/1d3b40c3b42fb3cc6b0192d34aba2c21a1efd369/pypdftk.py#L87-L123>
- <https://github.com/revolunet/pypdftk>
- <https://www.vulncheck.com/advisories/pypdftk-through-0.5-os-command-injection-via-pdf-and-output-paths>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/sicherheitsluecken/cve-2026-110636/) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI WID (CSAF)_