TI-2025-37344 Aliases CVE-2025-59956 GHSA-w64r-2g3w-w8w4

AgentAPI exposed user chat history via a DNS rebinding attack

MEDIUM 62CWE-350Published 2025-09-29 · Updated 2025-09-30

Key facts

Attack vector: Network
Privileges required: None
User interaction: Required
Attack complexity: Low
Impact type: Security bypass
Confidentiality · integrity · availability: High · None · None
Fix status: Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-290.

Summary

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV

EPSS 0.00426 37th percentileScored 2026-11-07

Public exploit Yes 2 exploit referencesTagged by NVD

Fix Fixed agentapi (coder): 0.4.0github.com/coder/agentapi (Go): 0.4.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: Poc
Automatable: No
Technical impact: Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
coder	agentapi	before 0.4.0	0.4.0	Patch available	CNA
—	github.com/coder/agentapi (Go)	before 0.4.0	0.4.0	Patch available	GHSA-w64r-2g3w-w8w4

agentapi Vendorcoder Affected before 0.4.0 Fixed in 0.4.0 Patch available CNA
github.com/coder/agentapi (Go) Vendor— Affected before 0.4.0 Fixed in 0.4.0 Patch available GHSA-w64r-2g3w-w8w4

CPE configurations NVD · 1

CPE	Versions	Role	Vendor
cpe:2.3:a:coder:agentapi::::::::	before 0.4.0	Vulnerable	coder

cpe:2.3:a:coder:agentapi:*:*:*:*:*:*:*:* Versions before 0.4.0 Vulnerable ·coder

Remediation

Fix · CNA agentapi (coder) Fixed in 0.4.0
Fix · GHSA-w64r-2g3w-w8w4 github.com/coder/agentapi (Go) Fixed in 0.4.0 Advisory →

Timeline

2026-10-02 Threatist record created from CVE-2025-59956
2026-10-03 Alias added: GHSA-w64r-2g3w-w8w4

References

Exploit 2

Patch 3

Advisory 1

https://nvd.nist.gov/vuln/detail/CVE-2025-59956

Other 4

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences