MechanicalSoup vulnerable to malicious web server reading arbitrary files on client using file input inside HTML form
Priority HIGH 66CWE-20Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- High · None · None
- Fix status
- Fixed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA and GitHub.
Summary
MechanicalSoup is a Python library for automating interaction with websites. Starting in version 0.2.0 and prior to version 1.3.0, a malicious web server can read arbitrary files on the client using a `<input type="file" ...>` inside HTML form. All users of MechanicalSoup's form submission are affected, unless they took very specific (and manual) steps to reset HTML form field values. Version 1.3.0 contains a patch for this issue.
Why it matters now
Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.01082 65th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed MechanicalSoup (MechanicalSoup): 1.3.0MechanicalSoup (PyPI): 1.3.0
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- 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 |
|---|---|---|---|---|---|
| MechanicalSoup | MechanicalSoup | 0.2.0 to before 1.3.0 | 1.3.0 | Patch available | CNA |
| — | MechanicalSoup (PyPI) | 0.2.0 to before 1.3.0 | 1.3.0 | Patch available | GHSA-x456-3ccm-m6j4 |
- MechanicalSoup VendorMechanicalSoup Affected 0.2.0 to before 1.3.0 Fixed in 1.3.0 Patch available CNA
- MechanicalSoup (PyPI) Vendor— Affected 0.2.0 to before 1.3.0 Fixed in 1.3.0 Patch available GHSA-x456-3ccm-m6j4
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:mechanicalsoup_project:mechanicalsoup:*:*:*:*:*:python:*:* | before 1.3.0 | Vulnerable | Mechanicalsoup Project |
- cpe:2.3:a:mechanicalsoup_project:mechanicalsoup:*:*:*:*:*:python:*:* Versions before 1.3.0 Vulnerable ·Mechanicalsoup Project
Remediation
- Fix · CNA MechanicalSoup (MechanicalSoup) Fixed in 1.3.0
- Fix · GHSA-x456-3ccm-m6j4 MechanicalSoup (PyPI) Fixed in 1.3.0 Advisory →
Vendor assessments
Timeline
- 2026-10-02 Threatist record created from CVE-2023-34457
- 2026-10-03 Alias added: GHSA-x456-3ccm-m6j4
References
Patch 1
Sources
- CVE-2023-34457 · CVE Program
- CVE-2023-34457 · NVD
- FIRST EPSS
- GHSA-x456-3ccm-m6j4 · GitHub Advisory Database · CC BY 4.0
- CVE-2023-34457 · 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