CVE-2026-67448
Mailpit: WebSocket origin check bypass via percent-encoded path (regression of CVE-2026-22689)
- Published
- Updated
- Reserved
- Assigned by
- GitHub_M
Description
Mailpit is an email testing tool and API for developers. From 1.29.0 until 1.30.6, Mailpit's server/server.go origin middleware checks the raw RequestURI for the /api/ prefix while Go's ServeMux routes using the percent-decoded URL path, and server/websockets/client.go configures websocket.Upgrader.CheckOrigin to return true. A malicious website can request /%61pi/events, skip corsOriginAccessControl(), reach the /api/events WebSocket handler, and receive live message IDs, Message-Id values, sender and recipient fields, subjects, tags, and body snippets from an unauthenticated default Mailpit instance after the user visits the site. This is a regression of the earlier WebSocket origin protection and does not affect deployments protected by --ui-auth-file. This issue is fixed in version 1.30.6.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | Medium6.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N |
| NVDNVD · Deferred | 3.1 | Medium6.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N |
- EPSS (exploitation in 30 days)
- 0.22% · top 87% of all CVEs (5 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 6.5.
Weakness
- CWE-177: Improper Handling of URL Encoding (Hex Encoding) (opens in a new tab)All about CWE-177 and its CVEs
- CWE-200: Exposure of Sensitive Information to an Unauthorized Actor (opens in a new tab)All about CWE-200 and its CVEs
- CWE-346: Origin Validation Error (opens in a new tab)All about CWE-346 and its CVEs
Affected products
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- Gogithub.com/axllent/mailpitGHSA-8r62-w5wh-fc5m (opens in a new tab)
References (3)
- https://github.com/axllent/mailpit/security/advisories/GHSA-8r62-w5wh-fc5m (opens in a new tab)x_refsource_CONFIRM
- https://github.com/axllent/mailpit/commit/fbe5e006c3f1682b819df58b4a932d7a84920be9 (opens in a new tab)x_refsource_MISC
- https://github.com/axllent/mailpit/releases/tag/v1.30.6 (opens in a new tab)x_refsource_MISC
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-8r62-w5wh-fc5m (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2026-67448)Record last updated .