FreeScout is a free help desk and shared inbox built with PHP's Laravel framework. Prior to version 1.8.223, an unauthenticated attacker can inject messages into any existing support conversation by sending a single email to the helpdesk's public address with a crafted `In-Reply-To` header. No credentials, tokens, or prior access are required. The injected message is rendered in the agent UI as a legitimate customer reply, the conversation is automatically reopened, and the `last_reply_from` field is set to the attacker's identity. Version 1.8.223 contains a fix.
Metrics
Affected Vendors & Products
References
History
Mon, 20 Jul 2026 22:30:00 +0000
| Type | Values Removed | Values Added |
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| First Time appeared |
Freescout Helpdesk
Freescout Helpdesk freescout |
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| Vendors & Products |
Freescout Helpdesk
Freescout Helpdesk freescout |
Mon, 20 Jul 2026 21:30:00 +0000
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| Metrics |
ssvc
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Mon, 20 Jul 2026 20:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | FreeScout is a free help desk and shared inbox built with PHP's Laravel framework. Prior to version 1.8.223, an unauthenticated attacker can inject messages into any existing support conversation by sending a single email to the helpdesk's public address with a crafted `In-Reply-To` header. No credentials, tokens, or prior access are required. The injected message is rendered in the agent UI as a legitimate customer reply, the conversation is automatically reopened, and the `last_reply_from` field is set to the attacker's identity. Version 1.8.223 contains a fix. | |
| Title | FreeScout Vulnerable to Unauthenticated Conversation Thread Injection via HMAC Length Bypass in FetchEmails | |
| Weaknesses | CWE-287 | |
| References |
| |
| Metrics |
cvssV3_1
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Status: PUBLISHED
Assigner: GitHub_M
Published:
Updated: 2026-07-20T20:15:26.874Z
Reserved: 2026-06-09T19:11:53.485Z
Link: CVE-2026-53591
Updated: 2026-07-20T20:15:22.271Z
No data.
No data.
OpenCVE Enrichment
Updated: 2026-07-20T22:15:03Z