CVE-2026-104380CWE-1385

CVE-2026-104380

Medium · published October 6, 2026

CVSS v3.1
5.3
EPSS
0%
Percentile
5.2
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
5.3 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
CVSS v4.0
Not supplied
EPSS
0.00163 · 5.2th percentile
Weakness
CWE-1385 · Missing Origin Validation in WebSockets
Published
2026-10-06T06:17Z
References (3)
https://metacpan.org/release/LNATION/Punk-0.55/changes · 9b29abf9-4ab0-4765-b253-1875cd9b441ehttps://metacpan.org/release/LNATION/Punk-0.55/diff/LNATION/Punk-0.54 · 9b29abf9-4ab0-4765-b253-1875cd9b441ehttp://www.openwall.com/lists/oss-security/2026/10/06/1 · af854a3a-2127-422b-91ae-364da2661108
EPSS history
Timeline
  • 07 OCT 03:39Z
    EPSS moved — → 0%
    epss
  • 06 OCT 01:13Z
    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
    cvelistv5