Vulnerability · Published Jan 10, 2026 · Assigned by GitHub_M
CVE-2026-22689Mailpit is vulnerable to Cross-Site WebSocket Hijacking (CSWSH) allowing unauthenticated access to emails
Medium 6.5
In plain English
A medium-severity security flaw in mailpit from axllent. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 15% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
Mailpit is an email testing tool and API for developers. Prior to version 1.28.2, the Mailpit WebSocket server is configured to accept connections from any origin. This lack of Origin header validation introduces a Cross-Site WebSocket Hijacking (CSWSH) vulnerability. An attacker can host a malicious website that, when visited by a developer running Mailpit locally, establishes a WebSocket connection to the victim's Mailpit instance (default ws://localhost:8025). This allows the attacker to intercept sensitive data such as email contents, headers, and server statistics in real-time. This issue has been patched in version 1.28.2.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Go | github.com/axllent/mailpit | 1.28.2 | GHSA-524m-q5m7-79mm |
| Go | github.com/axllent/mailpit | 0.0.0-20260110031614 | GHSA-524m-q5m7-79mm |
| Go | github.com/axllent/mailpit | 1.28.2 | GO-2026-4310 |
Affected products (as reported)
Weakness: CWE-1385 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N