CVE-2025-59956 (GCVE-0-2025-59956)
Vulnerability from cvelistv5
Published
2025-09-29 23:57
Modified
2025-09-30 14:14
Severity ?
6.5 (Medium) - CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
CWE
  • CWE-350 - Reliance on Reverse DNS Resolution for a Security-Critical Action
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.
References
security-advisories@github.comhttps://github.blog/security/application-security/localhost-dangers-cors-and-dns-rebinding
security-advisories@github.comhttps://github.com/coder/agentapi/commit/5c425c62447b8a9eac19e9fc5a2eae7f0803f149
security-advisories@github.comhttps://github.com/coder/agentapi/pull/49
security-advisories@github.comhttps://github.com/coder/agentapi/releases/tag/v0.4.0
security-advisories@github.comhttps://github.com/coder/agentapi/security/advisories/GHSA-w64r-2g3w-w8w4
security-advisories@github.comhttps://mcpsec.dev/advisories/2025-09-19-coder-chat-exfiltration
134c704f-9b21-4f2e-91b3-4a467353bcc0https://mcpsec.dev/advisories/2025-09-19-coder-chat-exfiltration/
Impacted products
Vendor Product Version
coder agentapi Version: < 0.4.0
 Create a notification for this product.
Show details on NVD website

To clipboard 

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2025-59956",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2025-09-30T14:14:39.407205Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2025-09-30T14:14:53.214Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "references": [
          {
            "tags": [
              "exploit"
            ],
            "url": "https://mcpsec.dev/advisories/2025-09-19-coder-chat-exfiltration/"
          }
        ],
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "agentapi",
          "vendor": "coder",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 0.4.0"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "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."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 6.5,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "REQUIRED",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-350",
              "description": "CWE-350: Reliance on Reverse DNS Resolution for a Security-Critical Action",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2025-09-29T23:57:08.133Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/coder/agentapi/security/advisories/GHSA-w64r-2g3w-w8w4",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/coder/agentapi/security/advisories/GHSA-w64r-2g3w-w8w4"
        },
        {
          "name": "https://github.com/coder/agentapi/pull/49",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/coder/agentapi/pull/49"
        },
        {
          "name": "https://github.com/coder/agentapi/commit/5c425c62447b8a9eac19e9fc5a2eae7f0803f149",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/coder/agentapi/commit/5c425c62447b8a9eac19e9fc5a2eae7f0803f149"
        },
        {
          "name": "https://github.blog/security/application-security/localhost-dangers-cors-and-dns-rebinding",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.blog/security/application-security/localhost-dangers-cors-and-dns-rebinding"
        },
        {
          "name": "https://github.com/coder/agentapi/releases/tag/v0.4.0",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/coder/agentapi/releases/tag/v0.4.0"
        },
        {
          "name": "https://mcpsec.dev/advisories/2025-09-19-coder-chat-exfiltration",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://mcpsec.dev/advisories/2025-09-19-coder-chat-exfiltration"
        }
      ],
      "source": {
        "advisory": "GHSA-w64r-2g3w-w8w4",
        "discovery": "UNKNOWN"
      },
      "title": "AgentAPI exposed user chat history via a DNS rebinding attack"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2025-59956",
    "datePublished": "2025-09-29T23:57:08.133Z",
    "dateReserved": "2025-09-23T14:33:49.506Z",
    "dateUpdated": "2025-09-30T14:14:53.214Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.1",
  "vulnerability-lookup:meta": {
    "nvd": "{\"cve\":{\"id\":\"CVE-2025-59956\",\"sourceIdentifier\":\"security-advisories@github.com\",\"published\":\"2025-09-30T11:37:41.743\",\"lastModified\":\"2025-10-02T19:12:42.843\",\"vulnStatus\":\"Awaiting Analysis\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"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.\"}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"security-advisories@github.com\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N\",\"baseScore\":6.5,\"baseSeverity\":\"MEDIUM\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"REQUIRED\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"NONE\",\"availabilityImpact\":\"NONE\"},\"exploitabilityScore\":2.8,\"impactScore\":3.6}]},\"weaknesses\":[{\"source\":\"security-advisories@github.com\",\"type\":\"Secondary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-350\"}]}],\"references\":[{\"url\":\"https://github.blog/security/application-security/localhost-dangers-cors-and-dns-rebinding\",\"source\":\"security-advisories@github.com\"},{\"url\":\"https://github.com/coder/agentapi/commit/5c425c62447b8a9eac19e9fc5a2eae7f0803f149\",\"source\":\"security-advisories@github.com\"},{\"url\":\"https://github.com/coder/agentapi/pull/49\",\"source\":\"security-advisories@github.com\"},{\"url\":\"https://github.com/coder/agentapi/releases/tag/v0.4.0\",\"source\":\"security-advisories@github.com\"},{\"url\":\"https://github.com/coder/agentapi/security/advisories/GHSA-w64r-2g3w-w8w4\",\"source\":\"security-advisories@github.com\"},{\"url\":\"https://mcpsec.dev/advisories/2025-09-19-coder-chat-exfiltration\",\"source\":\"security-advisories@github.com\"},{\"url\":\"https://mcpsec.dev/advisories/2025-09-19-coder-chat-exfiltration/\",\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\"}]}}",
    "vulnrichment": {
      "containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2025-59956\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"poc\"}, {\"Automatable\": \"no\"}, {\"Technical Impact\": \"partial\"}], \"version\": \"2.0.3\", \"timestamp\": \"2025-09-30T14:14:39.407205Z\"}}}], \"references\": [{\"url\": \"https://mcpsec.dev/advisories/2025-09-19-coder-chat-exfiltration/\", \"tags\": [\"exploit\"]}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2025-09-30T14:14:47.754Z\"}}], \"cna\": {\"title\": \"AgentAPI exposed user chat history via a DNS rebinding attack\", \"source\": {\"advisory\": \"GHSA-w64r-2g3w-w8w4\", \"discovery\": \"UNKNOWN\"}, \"metrics\": [{\"cvssV3_1\": {\"scope\": \"UNCHANGED\", \"version\": \"3.1\", \"baseScore\": 6.5, \"attackVector\": \"NETWORK\", \"baseSeverity\": \"MEDIUM\", \"vectorString\": \"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N\", \"integrityImpact\": \"NONE\", \"userInteraction\": \"REQUIRED\", \"attackComplexity\": \"LOW\", \"availabilityImpact\": \"NONE\", \"privilegesRequired\": \"NONE\", \"confidentialityImpact\": \"HIGH\"}}], \"affected\": [{\"vendor\": \"coder\", \"product\": \"agentapi\", \"versions\": [{\"status\": \"affected\", \"version\": \"\u003c 0.4.0\"}]}], \"references\": [{\"url\": \"https://github.com/coder/agentapi/security/advisories/GHSA-w64r-2g3w-w8w4\", \"name\": \"https://github.com/coder/agentapi/security/advisories/GHSA-w64r-2g3w-w8w4\", \"tags\": [\"x_refsource_CONFIRM\"]}, {\"url\": \"https://github.com/coder/agentapi/pull/49\", \"name\": \"https://github.com/coder/agentapi/pull/49\", \"tags\": [\"x_refsource_MISC\"]}, {\"url\": \"https://github.com/coder/agentapi/commit/5c425c62447b8a9eac19e9fc5a2eae7f0803f149\", \"name\": \"https://github.com/coder/agentapi/commit/5c425c62447b8a9eac19e9fc5a2eae7f0803f149\", \"tags\": [\"x_refsource_MISC\"]}, {\"url\": \"https://github.blog/security/application-security/localhost-dangers-cors-and-dns-rebinding\", \"name\": \"https://github.blog/security/application-security/localhost-dangers-cors-and-dns-rebinding\", \"tags\": [\"x_refsource_MISC\"]}, {\"url\": \"https://github.com/coder/agentapi/releases/tag/v0.4.0\", \"name\": \"https://github.com/coder/agentapi/releases/tag/v0.4.0\", \"tags\": [\"x_refsource_MISC\"]}, {\"url\": \"https://mcpsec.dev/advisories/2025-09-19-coder-chat-exfiltration\", \"name\": \"https://mcpsec.dev/advisories/2025-09-19-coder-chat-exfiltration\", \"tags\": [\"x_refsource_MISC\"]}], \"descriptions\": [{\"lang\": \"en\", \"value\": \"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.\"}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-350\", \"description\": \"CWE-350: Reliance on Reverse DNS Resolution for a Security-Critical Action\"}]}], \"providerMetadata\": {\"orgId\": \"a0819718-46f1-4df5-94e2-005712e83aaa\", \"shortName\": \"GitHub_M\", \"dateUpdated\": \"2025-09-29T23:57:08.133Z\"}}}",
      "cveMetadata": "{\"cveId\": \"CVE-2025-59956\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2025-09-30T14:14:53.214Z\", \"dateReserved\": \"2025-09-23T14:33:49.506Z\", \"assignerOrgId\": \"a0819718-46f1-4df5-94e2-005712e83aaa\", \"datePublished\": \"2025-09-29T23:57:08.133Z\", \"assignerShortName\": \"GitHub_M\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.1"
    }
  }
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Sightings

Author Source Type Date

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
  • Confirmed: The vulnerability is confirmed from an analyst perspective.
  • Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
  • Patched: This vulnerability was successfully patched by the user reporting the sighting.
  • Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
  • Not confirmed: The user expresses doubt about the veracity of the vulnerability.
  • Not patched: This vulnerability was not successfully patched by the user reporting the sighting.