CVE-2025-59956 | AgentAPI exposed user chat history via a DNS rebinding attack

Exp

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.

Published: 2025-09-30 Last update: 2025-10-08 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2025-59956 is rated Exploit Available (50/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.06%). Core evidence: 2 public exploit reference(s) are indexed (Exploit-DB). Mandatory action: Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2025-59956

EDB-ID Source Kind Published Link
nvd_ref exploit_tag Exploit-DB ↗
nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2025-59956

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-03-09 0.05% 0.06% +0.02%
2 2026-02-25 0.05% 0.05% -0.00%
3 2025-11-21 0.05%

Full EPSS history (6 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-59956

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.5 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
2.8 3.6 [email protected]

Weakness enumeration for CVE-2025-59956

GitHub Security Advisory for CVE-2025-59956

GHSA-w64r-2g3w-w8w4 · Severity: medium · Ecosystem: go — Coder AgentAPI exposed user chat history via a DNS rebinding attack

Affected software / configurations for CVE-2025-59956

Vendor Product Version Raw CPE
coder agentapi < 0.4.0 cpe:2.3:a:coder:agentapi:*:*:*:*:*:*:*:*

References for CVE-2025-59956

cvelogic Threat Intelligence