CVE-2026-22689 - Mailpit Plugin
CVE-2026-22689
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.
CVE-2026-22689
MEDIUM
CVSS 6.5
Published 2026-01-10
Updated 2026-02-18
AI Risk High (84/100)
Active Exploit: Likely
Published Exploit: Public exploit references found
Priority: P2 Urgent
Severity Band
MEDIUM
CVSS Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
Affected Components
1
Reference Links
2
AI Risk Engine
High (84/100)
Exploitability
High
Active Exploitation
Likely
Published Exploit Status
Public exploit references found
AI Context
Machine-generated threat intelligence
AI
Updated 16 days ago
AI enriched 16 days ago (2026-04-09 06:24 UTC)
Technical Summary
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…
Potential Impact
Severity is MEDIUM (CVSS 6.5). Depending on deployment context, affected components may be exposed to unauthorized actions or data integrity risk.
Exploitability Assessment
Exploitability is assessed as High based on published exploit references, remote code execution potential.
Primary risk drivers: published exploit references, remote code execution potential
Mitigation Recommendations
Validate affected product versions, prioritize patching, and monitor references for vendor remediation guidance. If immediate patching is not possible, apply compensating controls and limit exposure of vulnerable surfaces.
Detection & Monitoring
Track authentication anomalies, unexpected file writes, and suspicious plugin API activity around affected components.
Business Impact Lens
Prioritize remediation where affected components process customer data, admin sessions, or Internet-exposed workflows.