AgentAPI is an HTTP API for Claude Code, Goose, Aider, Gemini, Amp, and Codex. Versions 0.3.3 and below are susceptible to a client-side DNS rebinding attack when hosted over plain HTTP on localhost. An attacker can gain access to the /messages endpoint served by the Agent API. This allows for the unauthorized exfiltration of sensitive user data, specifically local message history, which can include secret keys, file system contents, and intellectual property the user was working on locally. This issue is fixed in version 0.4.0.
References
Link | Resource |
---|---|
https://github.blog/security/application-security/localhost-dangers-cors-and-dns-rebinding | Technical Description |
https://github.com/coder/agentapi/commit/5c425c62447b8a9eac19e9fc5a2eae7f0803f149 | Patch |
https://github.com/coder/agentapi/pull/49 | Issue Tracking Patch |
https://github.com/coder/agentapi/releases/tag/v0.4.0 | Release Notes |
https://github.com/coder/agentapi/security/advisories/GHSA-w64r-2g3w-w8w4 | Patch Vendor Advisory |
https://mcpsec.dev/advisories/2025-09-19-coder-chat-exfiltration | Exploit Third Party Advisory |
https://mcpsec.dev/advisories/2025-09-19-coder-chat-exfiltration/ | Exploit Third Party Advisory |
Configurations
History
08 Oct 2025, 15:05
Type | Values Removed | Values Added |
---|---|---|
CWE | CWE-290 | |
First Time |
Coder agentapi
Coder |
|
CPE | cpe:2.3:a:coder:agentapi:*:*:*:*:*:*:*:* | |
References | () https://github.blog/security/application-security/localhost-dangers-cors-and-dns-rebinding - Technical Description | |
References | () https://github.com/coder/agentapi/commit/5c425c62447b8a9eac19e9fc5a2eae7f0803f149 - Patch | |
References | () https://github.com/coder/agentapi/pull/49 - Issue Tracking, Patch | |
References | () https://github.com/coder/agentapi/releases/tag/v0.4.0 - Release Notes | |
References | () https://github.com/coder/agentapi/security/advisories/GHSA-w64r-2g3w-w8w4 - Patch, Vendor Advisory | |
References | () https://mcpsec.dev/advisories/2025-09-19-coder-chat-exfiltration - Exploit, Third Party Advisory | |
References | () https://mcpsec.dev/advisories/2025-09-19-coder-chat-exfiltration/ - Exploit, Third Party Advisory |
30 Sep 2025, 15:15
Type | Values Removed | Values Added |
---|---|---|
References |
|
30 Sep 2025, 11:37
Type | Values Removed | Values Added |
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New CVE |
Information
Published : 2025-09-30 11:37
Updated : 2025-10-08 15:05
NVD link : CVE-2025-59956
Mitre link : CVE-2025-59956
CVE.ORG link : CVE-2025-59956
JSON object : View
Products Affected
coder
- agentapi