WebDyne up to 3.21 PSGI API path traversal

Summaryinfo

A vulnerability, which was classified as critical, was found in WebDyne up to 3.21. This vulnerability affects unknown code of the component PSGI API. The manipulation results in path traversal. This vulnerability is cataloged as CVE-2026-78189. The attack may be launched remotely. There is no exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, was found in WebDyne up to 3.21. Affected is some unknown functionality of the component PSGI API. The manipulation with an unknown input leads to a path traversal vulnerability. CWE is classifying the issue as CWE-22. The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

WebDyne versions from 3.007 before 3.022 for Perl execute .psp files outside the document root via path traversal in the PSGI API route fallback. When a request matches no file, the PSGI handler retries it as an API route through api_filename. That keeps .. segments in the request path and only checks that the joined path starts with the document root, which a request for /../private passes. A remote attacker can run the embedded Perl in any .psp file the server can read, such as one uploaded to a directory outside the document root.

The advisory is shared for download at metacpan.org. This vulnerability is traded as CVE-2026-78189 since 08/23/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. There are neither technical details nor an exploit publicly available. The MITRE ATT&CK project declares the attack technique as T1006.

Upgrading to version 3.022 eliminates this vulnerability.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Name

• WebDyne

Version

• 3.0
• 3.1
• 3.2
• 3.3
• 3.4
• 3.5
• 3.6
• 3.7
• 3.8
• 3.9
• 3.10
• 3.11
• 3.12
• 3.13
• 3.14
• 3.15
• 3.16
• 3.17
• 3.18
• 3.19
• 3.20
• 3.21

CPE 2.3info

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CPE 2.2info

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Once again VulDB remains the best source for vulnerability data.

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