Vulnerability-Lookup

CVE-2026-40242 (GCVE-0-2026-40242)

Vulnerability from cvelistv5 – Published: 2026-04-10 20:34 – Updated: 2026-04-13 20:54

Shadowserver Previdian

Title

Arcane Unauthenticated SSRF with Conditional Response Reflection in Template Fetch Endpoint

Summary

Arcane is an interface for managing Docker containers, images, networks, and volumes. Prior to 1.17.3, the /api/templates/fetch endpoint accepts a caller-supplied url parameter and performs a server-side HTTP GET request to that URL without authentication and without URL scheme or host validation. The server's response is returned directly to the caller. type. This constitutes an unauthenticated SSRF vulnerability affecting any publicly reachable Arcane instance. This vulnerability is fixed in 1.17.3.

Severity

7.2 (High)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N

SSVC

Exploitation: poc Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-04-13 20:54 UTC

CWE

CWE-918 - Server-Side Request Forgery (SSRF)

Assigner

GitHub_M CNA under the mitre root

CNA scorecard C 72/100 over 7886 records in the last 180 days details

References

2 references

URL	Tags
https://github.com/getarcaneapp/arcane/security/a…	x_refsource_CONFIRM
https://github.com/getarcaneapp/arcane/releases/t…	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version	CPE status
getarcaneapp	arcane	Affected: < 1.17.3	guessed

Shadowserver

Known Exploited Vulnerability - GCVE BCP-07 Compliant

KEV entry ID: b7be420d-b459-4b41-9221-82b3eb0071cf

Vulnerability ID: CVE-2026-40242

Status: Confirmed

Status Updated: 2026-11-01 00:00 UTC

Exploited: Yes

Characteristics

Severity: 65.0

Timestamps

First Seen: 2026-09-17

Asserted: 2026-09-17

Last Seen: 2026-11-01

Scope

Asset Exposure: ['internet-facing']

Evidence

Type: Honeypot

Signal: In The Wild Attempts

Confidence: 70%

Source: shadowserver

Details

1D	1
Iot	no
Feed	Shadowserver Foundation honeypot/exploited-vulnerabilities
Type	http-scan
Class	other-software
7D Avg	0
Vendor	Arcane
30D Avg	0
90D Avg	0
Product	Arcane
Cisa Kev	no
Connections	2
Observation Date	2026-11-01
Vulnerability Class	CVSS
Vulnerability Score	6.5
Vulnerability Severity	Medium

References

Created: 2026-10-21 09:13 UTC | Updated: 2026-11-03 01:01 UTC

Previdian

Known Exploited Vulnerability - GCVE BCP-07 Compliant

KEV entry ID: 92838de3-d6e8-4d09-993e-6537e19b9f78

Vulnerability ID: CVE-2026-40242

Status: Confirmed

Status Updated: 2026-09-17 00:00 UTC

Exploited: Yes

Timestamps

First Seen: 2026-09-17

Asserted: 2026-09-17

Scope

Evidence

Type: Public Report

Signal: Successful Exploitation

Confidence: 70%

Source: previdian

Details

Feed	Previdian (previdian.com)
Title	Arcane Unauthenticated SSRF with Conditional Response Reflection in Template Fetch Endpoint
Cve Id	CVE-2026-40242
Vendor	Getarcaneapp
Ghsa Id	None
Product	arcane
Added Date	2026-09-17T00:00:00.000Z
Cvss Score	7.2
Epss Score	0.00621
Previous Ids
Cvss Severity	HIGH
Virtual Patch	False
Cvss Estimated	False
Epss Percentile	0.48118
Used In Malware	unknown
Vulnerability Id	CVE-2026-40242
Ahead Of Cisa Kev	None
Not Yet In Cisa Kev	True

References

Created: 2026-09-18 11:00 UTC | Updated: 2026-09-18 11:00 UTC

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-40242",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-04-13T20:54:32.958737Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-04-13T20:54:36.822Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "references": [
          {
            "tags": [
              "exploit"
            ],
            "url": "https://github.com/getarcaneapp/arcane/security/advisories/GHSA-ff24-4prj-gpmj"
          }
        ],
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "arcane",
          "vendor": "getarcaneapp",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 1.17.3"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Arcane is an interface for managing Docker containers, images, networks, and volumes. Prior to 1.17.3, the /api/templates/fetch endpoint accepts a caller-supplied url parameter and performs a server-side HTTP GET request to that URL without authentication and without URL scheme or host validation. The server\u0027s response is returned directly to the caller. type. This constitutes an unauthenticated SSRF vulnerability affecting any publicly reachable Arcane instance. This vulnerability is fixed in 1.17.3."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 7.2,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "LOW",
            "integrityImpact": "LOW",
            "privilegesRequired": "NONE",
            "scope": "CHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-918",
              "description": "CWE-918: Server-Side Request Forgery (SSRF)",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-04-10T20:34:12.777Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/getarcaneapp/arcane/security/advisories/GHSA-ff24-4prj-gpmj",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/getarcaneapp/arcane/security/advisories/GHSA-ff24-4prj-gpmj"
        },
        {
          "name": "https://github.com/getarcaneapp/arcane/releases/tag/v1.17.3",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/getarcaneapp/arcane/releases/tag/v1.17.3"
        }
      ],
      "source": {
        "advisory": "GHSA-ff24-4prj-gpmj",
        "discovery": "UNKNOWN"
      },
      "title": "Arcane Unauthenticated SSRF with Conditional Response Reflection in Template Fetch Endpoint"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-40242",
    "datePublished": "2026-04-10T20:34:12.777Z",
    "dateReserved": "2026-04-10T17:31:45.785Z",
    "dateUpdated": "2026-04-13T20:54:36.822Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-40242",
      "date": "2026-11-14",
      "epss": "0.00621",
      "percentile": "0.50357"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "product": "arcane",
                "vendor": "getarcaneapp",
                "versions": [
                  {
                    "status": "affected",
                    "version": "\u003c 1.17.3"
                  }
                ]
              }
            ],
            "source": "security-advisories@github.com"
          }
        ],
        "configurations": [
          {
            "nodes": [
              {
                "cpeMatch": [
                  {
                    "criteria": "cpe:2.3:a:getarcane:arcane:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "908A8D3F-26B0-4A9B-81F5-85D03CBF0E12",
                    "versionEndExcluding": "1.17.3",
                    "vulnerable": true
                  }
                ],
                "negate": false,
                "operator": "OR"
              }
            ]
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "Arcane is an interface for managing Docker containers, images, networks, and volumes. Prior to 1.17.3, the /api/templates/fetch endpoint accepts a caller-supplied url parameter and performs a server-side HTTP GET request to that URL without authentication and without URL scheme or host validation. The server\u0027s response is returned directly to the caller. type. This constitutes an unauthenticated SSRF vulnerability affecting any publicly reachable Arcane instance. This vulnerability is fixed in 1.17.3."
          },
          {
            "lang": "es",
            "value": "Arcane es una interfaz para gestionar contenedores Docker, im\u00e1genes, redes y vol\u00famenes. Anterior a la 1.17.3, el endpoint /API/templates/fetch acepta un par\u00e1metro url proporcionado por el llamador y realiza una solicitud HTTP GET del lado del servidor a esa URL sin autenticaci\u00f3n y sin validaci\u00f3n de esquema de URL o de host. La respuesta del servidor se devuelve directamente al llamador. tipo. Esto constituye una vulnerabilidad SSRF no autenticada que afecta a cualquier instancia de Arcane accesible p\u00fablicamente. Esta vulnerabilidad se corrige en la 1.17.3."
          }
        ],
        "id": "CVE-2026-40242",
        "lastModified": "2026-10-26T21:10:00.170",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "NETWORK",
                "availabilityImpact": "NONE",
                "baseScore": 7.2,
                "baseSeverity": "HIGH",
                "confidentialityImpact": "LOW",
                "integrityImpact": "LOW",
                "privilegesRequired": "NONE",
                "scope": "CHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N",
                "version": "3.1"
              },
              "exploitabilityScore": 3.9,
              "impactScore": 2.7,
              "source": "security-advisories@github.com",
              "type": "Secondary"
            },
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "NETWORK",
                "availabilityImpact": "NONE",
                "baseScore": 6.5,
                "baseSeverity": "MEDIUM",
                "confidentialityImpact": "LOW",
                "integrityImpact": "LOW",
                "privilegesRequired": "NONE",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N",
                "version": "3.1"
              },
              "exploitabilityScore": 3.9,
              "impactScore": 2.5,
              "source": "nvd@nist.gov",
              "type": "Primary"
            }
          ],
          "ssvcV203": [
            {
              "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "ssvcData": {
                "id": "CVE-2026-40242",
                "options": [
                  {
                    "exploitation": "poc"
                  },
                  {
                    "automatable": "yes"
                  },
                  {
                    "technicalImpact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-04-13T20:54:32.958737Z",
                "version": "2.0.3"
              }
            }
          ]
        },
        "published": "2026-04-10T21:16:27.747",
        "references": [
          {
            "source": "security-advisories@github.com",
            "tags": [
              "Release Notes"
            ],
            "url": "https://github.com/getarcaneapp/arcane/releases/tag/v1.17.3"
          },
          {
            "source": "security-advisories@github.com",
            "tags": [
              "Exploit",
              "Vendor Advisory"
            ],
            "url": "https://github.com/getarcaneapp/arcane/security/advisories/GHSA-ff24-4prj-gpmj"
          },
          {
            "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
            "tags": [
              "Exploit",
              "Vendor Advisory"
            ],
            "url": "https://github.com/getarcaneapp/arcane/security/advisories/GHSA-ff24-4prj-gpmj"
          }
        ],
        "sourceIdentifier": "security-advisories@github.com",
        "vulnStatus": "Analyzed",
        "weaknesses": [
          {
            "description": [
              {
                "lang": "en",
                "value": "CWE-918"
              }
            ],
            "source": "security-advisories@github.com",
            "type": "Secondary"
          }
        ]
      }
    },
    "redhat_vex": {
      "current_release_date": "2026-04-14T01:22:31+00:00",
      "cve": "CVE-2026-40242",
      "id": "CVE-2026-40242",
      "initial_release_date": "2026-01-01T00:00:00+00:00",
      "product_status:known_not_affected": "1",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "Arcane Unauthenticated SSRF with Conditional Response Reflection in Template Fetch Endpoint",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-40242.json",
      "version": "3"
    },
    "vulnrichment": {
      "containers": {
        "adp": [
          {
            "metrics": [
              {
                "other": {
                  "content": {
                    "id": "CVE-2026-40242",
                    "options": [
                      {
                        "Exploitation": "poc"
                      },
                      {
                        "Automatable": "yes"
                      },
                      {
                        "Technical Impact": "partial"
                      }
                    ],
                    "role": "CISA Coordinator",
                    "timestamp": "2026-04-13T20:54:32.958737Z",
                    "version": "2.0.3"
                  },
                  "type": "ssvc"
                }
              }
            ],
            "providerMetadata": {
              "dateUpdated": "2026-04-13T20:54:27.568Z",
              "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "shortName": "CISA-ADP"
            },
            "references": [
              {
                "tags": [
                  "exploit"
                ],
                "url": "https://github.com/getarcaneapp/arcane/security/advisories/GHSA-ff24-4prj-gpmj"
              }
            ],
            "title": "CISA ADP Vulnrichment"
          }
        ],
        "cna": {
          "affected": [
            {
              "product": "arcane",
              "vendor": "getarcaneapp",
              "versions": [
                {
                  "status": "affected",
                  "version": "\u003c 1.17.3"
                }
              ]
            }
          ],
          "descriptions": [
            {
              "lang": "en",
              "value": "Arcane is an interface for managing Docker containers, images, networks, and volumes. Prior to 1.17.3, the /api/templates/fetch endpoint accepts a caller-supplied url parameter and performs a server-side HTTP GET request to that URL without authentication and without URL scheme or host validation. The server\u0027s response is returned directly to the caller. type. This constitutes an unauthenticated SSRF vulnerability affecting any publicly reachable Arcane instance. This vulnerability is fixed in 1.17.3."
            }
          ],
          "metrics": [
            {
              "cvssV3_1": {
                "attackComplexity": "LOW",
                "attackVector": "NETWORK",
                "availabilityImpact": "NONE",
                "baseScore": 7.2,
                "baseSeverity": "HIGH",
                "confidentialityImpact": "LOW",
                "integrityImpact": "LOW",
                "privilegesRequired": "NONE",
                "scope": "CHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N",
                "version": "3.1"
              }
            }
          ],
          "problemTypes": [
            {
              "descriptions": [
                {
                  "cweId": "CWE-918",
                  "description": "CWE-918: Server-Side Request Forgery (SSRF)",
                  "lang": "en",
                  "type": "CWE"
                }
              ]
            }
          ],
          "providerMetadata": {
            "dateUpdated": "2026-04-10T20:34:12.777Z",
            "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
            "shortName": "GitHub_M"
          },
          "references": [
            {
              "name": "https://github.com/getarcaneapp/arcane/security/advisories/GHSA-ff24-4prj-gpmj",
              "tags": [
                "x_refsource_CONFIRM"
              ],
              "url": "https://github.com/getarcaneapp/arcane/security/advisories/GHSA-ff24-4prj-gpmj"
            },
            {
              "name": "https://github.com/getarcaneapp/arcane/releases/tag/v1.17.3",
              "tags": [
                "x_refsource_MISC"
              ],
              "url": "https://github.com/getarcaneapp/arcane/releases/tag/v1.17.3"
            }
          ],
          "source": {
            "advisory": "GHSA-ff24-4prj-gpmj",
            "discovery": "UNKNOWN"
          },
          "title": "Arcane Unauthenticated SSRF with Conditional Response Reflection in Template Fetch Endpoint"
        }
      },
      "cveMetadata": {
        "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "assignerShortName": "GitHub_M",
        "cveId": "CVE-2026-40242",
        "datePublished": "2026-04-10T20:34:12.777Z",
        "dateReserved": "2026-04-10T17:31:45.785Z",
        "dateUpdated": "2026-04-13T20:54:36.822Z",
        "state": "PUBLISHED"
      },
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}

FKIE_CVE-2026-40242

Vulnerability from fkie_nvd - Published: 2026-04-10 21:16 - Updated: 2026-10-26 21:10

Shadowserver Previdian

Severity

7.2 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
6.5 (Medium) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

Summary

References

URL	Tags
security-advisories@github.com	https://github.com/getarcaneapp/arcane/releases/tag/v1.17.3	Release Notes
security-advisories@github.com	https://github.com/getarcaneapp/arcane/security/advisories/GHSA-ff24-4prj-gpmj	Exploit, Vendor Advisory
134c704f-9b21-4f2e-91b3-4a467353bcc0	https://github.com/getarcaneapp/arcane/security/advisories/GHSA-ff24-4prj-gpmj	Exploit, Vendor Advisory

Impacted products

	Vendor	Product	Version
	getarcane	arcane	*

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "arcane",
          "vendor": "getarcaneapp",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 1.17.3"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:getarcane:arcane:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "908A8D3F-26B0-4A9B-81F5-85D03CBF0E12",
              "versionEndExcluding": "1.17.3",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Arcane is an interface for managing Docker containers, images, networks, and volumes. Prior to 1.17.3, the /api/templates/fetch endpoint accepts a caller-supplied url parameter and performs a server-side HTTP GET request to that URL without authentication and without URL scheme or host validation. The server\u0027s response is returned directly to the caller. type. This constitutes an unauthenticated SSRF vulnerability affecting any publicly reachable Arcane instance. This vulnerability is fixed in 1.17.3."
    },
    {
      "lang": "es",
      "value": "Arcane es una interfaz para gestionar contenedores Docker, im\u00e1genes, redes y vol\u00famenes. Anterior a la 1.17.3, el endpoint /API/templates/fetch acepta un par\u00e1metro url proporcionado por el llamador y realiza una solicitud HTTP GET del lado del servidor a esa URL sin autenticaci\u00f3n y sin validaci\u00f3n de esquema de URL o de host. La respuesta del servidor se devuelve directamente al llamador. tipo. Esto constituye una vulnerabilidad SSRF no autenticada que afecta a cualquier instancia de Arcane accesible p\u00fablicamente. Esta vulnerabilidad se corrige en la 1.17.3."
    }
  ],
  "id": "CVE-2026-40242",
  "lastModified": "2026-10-26T21:10:00.170",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 7.2,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "LOW",
          "integrityImpact": "LOW",
          "privilegesRequired": "NONE",
          "scope": "CHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 2.7,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      },
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 6.5,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "LOW",
          "integrityImpact": "LOW",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 2.5,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-40242",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-04-13T20:54:32.958737Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-04-10T21:16:27.747",
  "references": [
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Release Notes"
      ],
      "url": "https://github.com/getarcaneapp/arcane/releases/tag/v1.17.3"
    },
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Exploit",
        "Vendor Advisory"
      ],
      "url": "https://github.com/getarcaneapp/arcane/security/advisories/GHSA-ff24-4prj-gpmj"
    },
    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "tags": [
        "Exploit",
        "Vendor Advisory"
      ],
      "url": "https://github.com/getarcaneapp/arcane/security/advisories/GHSA-ff24-4prj-gpmj"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-918"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Secondary"
    }
  ]
}

GHSA-FF24-4PRJ-GPMJ

Vulnerability from github – Published: 2026-04-10 20:59 – Updated: 2026-07-21 14:02

Summary

Arcane has Unauthenticated SSRF with Conditional Response Reflection in Template Fetch Endpoint

Details

Summary

The /api/templates/fetch endpoint accepts a caller-supplied url parameter and performs a server-side HTTP GET request to that URL without authentication and without URL scheme or host validation. The server's response is returned directly to the caller. type. This constitutes an unauthenticated SSRF vulnerability affecting any publicly reachable Arcane instance.

Details

No allowlist or denylist of destination hosts/CIDRs
No requirement for the caller to be authenticated

Response handling produces four distinct outcomes observable by the caller: - Valid JSON targets return a fully reflected response body if the returned fields fit the expected internal struct - Non-JSON HTTP 200 responses produce an error leaking the first byte of the response ("Invalid JSON response: invalid character '<'...") - Non-200 responses leak the HTTP status code - TCP-level failures distinguish between closed ports ("connection refused") and filtered ones ("i/o timeout")

PoC

Send an unauthenticated GET request to /api/templates/fetch, passing the target URL as the url query parameter.

Impact

Unauthenticated port scanning of internal networks
Access to internal HTTP services not exposed to the public internet (service discovery endpoints, internal dashboards, Kubernetes API)

Severity

7.2 (High)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N

Show details on source website

JSON

To clipboard

{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 1.17.2"
      },
      "package": {
        "ecosystem": "Go",
        "name": "github.com/getarcaneapp/arcane/backend"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.17.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-40242"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-918"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-04-10T20:59:27Z",
    "nvd_published_at": "2026-04-10T21:16:27Z",
    "severity": "HIGH"
  },
  "details": "### Summary\nThe /api/templates/fetch endpoint accepts a caller-supplied url parameter and performs a server-side HTTP GET request to that URL without authentication and without URL scheme or host validation. The server\u0027s response is returned directly to the caller. type. This constitutes an unauthenticated SSRF vulnerability affecting any publicly reachable Arcane instance.\n\n### Details\n- No allowlist or denylist of destination hosts/CIDRs\n- No requirement for the caller to be authenticated\n\nResponse handling produces four distinct outcomes observable by the caller: \n- Valid JSON targets return a fully reflected response body if the returned fields fit the expected internal struct\n- Non-JSON HTTP 200 responses produce an error leaking the first byte of the response (`\"Invalid JSON response: invalid character \u0027\u003c\u0027...\"`)\n- Non-200 responses leak the HTTP status code\n- TCP-level failures distinguish between closed ports (`\"connection refused\"`) and filtered ones (`\"i/o timeout\"`)\n\n### PoC\nSend an unauthenticated GET request to `/api/templates/fetch`, passing the target URL as the `url` query parameter.\n\n\u003cimg width=\"1041\" height=\"375\" alt=\"image\" src=\"https://github.com/user-attachments/assets/f9fd475e-90b0-4dec-95e1-0af6263f5bb5\" /\u003e\n\n### Impact\n- Unauthenticated port scanning of internal networks\n- Access to internal HTTP services not exposed to the public internet (service discovery endpoints, internal dashboards, Kubernetes API)",
  "id": "GHSA-ff24-4prj-gpmj",
  "modified": "2026-07-21T14:02:57Z",
  "published": "2026-04-10T20:59:27Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/getarcaneapp/arcane/security/advisories/GHSA-ff24-4prj-gpmj"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-40242"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/getarcaneapp/arcane"
    },
    {
      "type": "WEB",
      "url": "https://github.com/getarcaneapp/arcane/releases/tag/v1.17.3"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Arcane has Unauthenticated SSRF with Conditional Response Reflection in Template Fetch Endpoint"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

Order JSON

How durations are calculated

Following the VTEM framework (Black Hat USA 2015), time to patch starts when the vendor or a coordinator was informed, total time to patch at discovery, and disclosure to patch at public disclosure; vendor response time runs from the report to its acknowledgement. Time to exploit and time unpatched start at the earliest discovery or report, falling back to public disclosure. Unpatched time ends at the first recorded patch, or the calculation time when no patch is recorded. Exploitation to patch shows the interval between those two events; a published proof of concept is a public exploit, not exploitation.

Each result shows its source dates. A negative interval means the end event came first; when date-only inputs leave the order open, the result says so. Date-only inputs are approximate. The earliest evidence wins: KEV report dates and sightings are labelled as such. Records describing another vulnerability are listed but never calculated from, and a PoC alone does not establish exploitation. Missing patch evidence does not prove that no patch exists. Filters below change the event list only.

Publication & reservation Sightings KEV catalogs Other timestamps

Loading timeline…

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

Action not permitted

CVE-2026-40242 (GCVE-0-2026-40242)

Shadowserver

Known Exploited Vulnerability - GCVE BCP-07 Compliant

Characteristics

Timestamps

Scope

Evidence

Honeypot In The Wild Attempts Confidence: 70% Source: shadowserver

Details

References

Previdian

Known Exploited Vulnerability - GCVE BCP-07 Compliant

Timestamps

Scope

Evidence

Public Report Successful Exploitation Confidence: 70% Source: previdian

Details

References

FKIE_CVE-2026-40242

GHSA-FF24-4PRJ-GPMJ

Summary

Details

PoC

Impact

Tags

Sightings

Nomenclature

Vulnerability timeline

Related by attack behaviour