DNS Rebinding Affecting rmcp package, versions <1.4.0
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Test your applications- Snyk IDSNYK-RUST-RMCP-16599166
- published9 May 2026
- disclosed6 May 2026
- creditJLLeitschuh
Introduced: 6 May 2026
NewCVE-2026-42559 (opens in a new tab)How to fix?
Upgrade rmcp to version 1.4.0 or higher.
Overview
Affected versions of this package are vulnerable to DNS Rebinding via the Host header validation process. An attacker can gain unauthorized access to internal resources and potentially execute arbitrary code by convincing a user to visit a malicious website, which then sends authenticated requests to a server running on a private or loopback interface through a DNS rebinding attack.
Workaround
This vulnerability can be mitigated by placing the server behind a reverse proxy configured to reject requests with unexpected Host headers, or by avoiding binding the server to 0.0.0.0 without such a proxy.