CPANSA-Punk-2026-104380: Punk vulnerability
| Publisher | giterlizzi | Document category | csaf_security_advisory |
|---|---|---|---|
| Initial release date | 2026-10-06T00:00:00 | Engine | CSAF Perl Toolkit 0.26 |
| Current release date | 2026-10-06T00:00:00 | Build Date | |
| Current version | 1 | Status | final |
| CVSS v3.1 Base Score | 5.3 | Severity | Medium |
| Original language | Language | en | |
| Also referred to | |||
Vulnerability Description
Punk versions from 0.48 before 0.55 for Perl route Extended CONNECT requests to any GET route without an Origin check in ps_serve_one.
On HTTP/2 and HTTP/3 a WebSocket handshake arrives as an Extended CONNECT, which is matched as a GET and so reaches every GET route, API operation and mount. The Origin check runs only when a websocket route matches. On this transport the handler's status is the handshake response, and a 2xx accepts it.
A cross-origin page can open a WebSocket to any path and learn from its open or error event whether that path returns 2xx.
Vulnerabilities
CVE-2026-104380
Vulnerability DescriptionPunk versions from 0.48 before 0.55 for Perl route Extended CONNECT requests to any GET route without an Origin check in ps_serve_one.
On HTTP/2 and HTTP/3 a WebSocket handshake arrives as an Extended CONNECT, which is matched as a GET and so reaches every GET route, API operation and mount. The Origin check runs only when a websocket route matches. On this transport the handler's status is the handshake response, and a 2xx accepts it.
A cross-origin page can open a WebSocket to any path and learn from its open or error event whether that path returns 2xx.
| Weakness | CWE-1385 : Missing Origin Validation in WebSockets |
|---|
Product status
Known affected
| Product | Score | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Punk greater than or equal 0.48 and less than 0.55 |
|
Fixed
- Punk greater than or equal 0.55
giterlizzi
Namespace: https://github.com/giterlizzi/
gdt@cpan.org
References
- CPANSA-Punk-2026-104380 JSON self
https://raw.githubusercontent.com/giterlizzi/perl-CPANSA-CSAF/develop/csaf/white/2026/cpansa-punk-2026-104380.json - https://metacpan.org/release/LNATION/Punk-0.55/changes external
https://metacpan.org/release/LNATION/Punk-0.55/changes - https://metacpan.org/release/LNATION/Punk-0.55/diff/LNATION/Punk-0.54 external
https://metacpan.org/release/LNATION/Punk-0.55/diff/LNATION/Punk-0.54 - http://www.openwall.com/lists/oss-security/2026/10/06/1 external
http://www.openwall.com/lists/oss-security/2026/10/06/1 - CVE-2026-104380 (NVD) external
https://nvd.nist.gov/vuln/detail/CVE-2026-104380
Revision history
| Version | Date of the revision | Summary of the revision |
|---|---|---|
| 1 | Tue Oct 6 00:00:00 2026 | First release |
Sharing rules
TLP:WHITE
For the TLP version see: https://www.first.org/tlp/