CVE-2026-53591
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
CVSS
8.6
High
EPSS
—
KEV
—
Exploit Today
0
0-100
Published: Jul 20, 2026 · Last modified: Jul 20, 2026 · CWE-287
Not enough EPSS history yet.
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.