VulnerabilityPublished 31 Oct 2026

CVE-2026-78189: WebDyne versions from 3.007 before 3.022 for Perl execute .psp files outside the document root via

Source GCVE Database

Compare

Authoritative record:CVE-2026-78189· High

Not known to be exploited : upgrade to 3.022 soon.

Data as of 31 Oct 2026, 18:09 UTC

Severity

High

Rated High by Threat Radar's AI analysis · CVSS not yet scored by NVD

Thin evidence

One scorer or none

Patch: Available – fixed in 3.022

Exploitation evidence

Disclosed: evidence found.
CVE published 31 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 31 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponized: A Metasploit exploit module or Exploit-DB entry exists (Metasploit scanner modules do not count), or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

ghsa-vhwh-fhm6-mq7v

What to do

Upgrade WebDyne (Perl module) to 3.022.

Affected software

Product	Affected	Fixed in
WebDyne	Affected >=3.007 <3.022	Fixed in 3.022
CPANWebDyne`pkg:cpan/WebDyne`Other threats	Affected >=3.007 <3.022	Fixed in 3.022

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

If you cannot patch yet, restrict access to sensitive directories and files outside the document root and consider disabling the vulnerable PSGI API route fallback if possible.

Description

WebDyne versions from 3.007 up to but not including 3.022 for Perl contain a path traversal vulnerability in the PSGI API route fallback. This flaw allows remote attackers to execute .psp files located outside the document root by exploiting insufficient path validation. The PSGI handler retries unmatched requests as API routes without properly sanitizing '..' segments, enabling access to files outside the intended directory.

Impact

An attacker can remotely execute embedded Perl code in any .psp file accessible to the server outside the document root. This can lead to unauthorized code execution and potentially full compromise of the affected system.

Summary

The vulnerability exists in WebDyne Perl versions 3.007 before 3.022 where the PSGI API route fallback mechanism improperly handles path traversal sequences. When a request does not match any file, the PSGI handler attempts to process it as an API route by joining the request path with the document root but only checks that the resulting path starts with the document root. This check is insufficient because requests like '/../private' pass the check, allowing attackers to access and execute .psp files outside the document root. This enables remote code execution of embedded Perl code in these files if the server can read them.

CWE-22Improper Limitation of a Pathname to a Restricted Directory (Path Traversal) (opens in a new tab)
Base weaknessLikelihood of exploit: HighCWE Top 25 (2025): #6OWASP Top 10 A01:2025: Broken Access Control (opens in a new tab)
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.
Implementation · Input Validation
Assume all input is malicious. Use an "accept known good" input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.
Architecture and Design
For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks…
Implementation · Input Validation
Inputs should be decoded and canonicalized to the application's current internal representation before being validated (CWE-180). Make sure that the application does not decode the same input twice (CWE-174).
OWASP Cheat Sheets
Authorization (opens in a new tab)
OWASP ASVS 4.0.3
V12.3.1 (opens in a new tab)
Attack patterns
Path Traversal (opens in a new tab)
Using Slashes and URL Encoding Combined to Bypass Validation Logic (opens in a new tab)
Manipulating Web Input to File System Calls (opens in a new tab)
Using Escaped Slashes in Alternate Encoding (opens in a new tab)
Using Slashes in Alternate Encoding (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

Community reviews

Loading reviews…

Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 31 Oct 2026, 18:09 UTC

WeaknessesCWE-22

Technical details

References

Community reviews

Related threats