---
id: CVE-2026-104380
title: >-
  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 …
summary: >-
  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 …
severity: medium
cvss: 5.3
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N'
cwe:
  - CWE-1385
product: Punk
affected:
  - Punk >= 0.48 < 0.55
published: '2026-10-06'
updated: '2026-10-06'
sourceUpdated: '2026-10-06T15:03:59.427'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-104380'
references:
  - url: 'https://metacpan.org/release/LNATION/Punk-0.55/changes'
    label: 9b29abf9-4ab0-4765-b253-1875cd9b441e
  - url: 'https://metacpan.org/release/LNATION/Punk-0.55/diff/LNATION/Punk-0.54'
    label: 9b29abf9-4ab0-4765-b253-1875cd9b441e
  - url: 'http://www.openwall.com/lists/oss-security/2026/10/06/1'
    label: af854a3a-2127-422b-91ae-364da2661108
tags:
  - nvd
  - cve.org
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-10-06T13:14:06.093601Z'
ingestedAt: '2026-10-06T01:38:44.801Z'
epss: 0.00163
epssPercentile: 0.05511
---

## Overview

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.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.