CVE-2026-78189

CRITICALCVSS 9.8/10EPSS 0.25%

Last modified

CVE-2026-78189 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. 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 .. EPSS estimates a 0.25% chance of exploitation in the next 30 days.

Description

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.

Metrics

EPSS Probability
0.25%

16.3th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Source: CNA advisory (CVE.org). NVD analysis pending.

VendorProductVersions
——>= 3.007, < 3.022

References

Timeline

Published
Last Modified
Status
Deferred

Frequently Asked Questions

What is CVE-2026-78189?
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.
How severe is CVE-2026-78189?
CVE-2026-78189 has a CVSS score of 9.8/10 (CRITICAL severity). The EPSS model estimates a 0.25% probability of exploitation in the next 30 days.
How do I fix CVE-2026-78189?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

How Strix Helps

Related CVEs from 2026

Are you affected by CVE-2026-78189?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST