FKIE_CVE-2021-26074

Vulnerability from fkie_nvd - Published: 2021-04-16 03:15 - Updated: 2026-06-17 03:42
Severity
6.5 (Medium) - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
6.5 (Medium) - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
Summary
Broken Authentication in Atlassian Connect Spring Boot (ACSB) from version 1.1.0 before version 2.1.3: Atlassian Connect Spring Boot is a Java Spring Boot package for building Atlassian Connect apps. Authentication between Atlassian products and the Atlassian Connect Spring Boot app occurs with a server-to-server JWT or a context JWT. Atlassian Connect Spring Boot versions from version 1.1.0 before version 2.1.3 erroneously accept context JWTs in lifecycle endpoints (such as installation) where only server-to-server JWTs should be accepted, permitting an attacker to send authenticated re-installation events to an app.
References
security@atlassian.comhttps://community.developer.atlassian.com/t/action-required-atlassian-connect-vulnerability-allows-bypass-of-app-qsh-verification-via-context-jwts/47072Vendor Advisory
security@atlassian.comhttps://confluence.atlassian.com/pages/viewpage.action?pageId=1051986106Vendor Advisory
af854a3a-2127-422b-91ae-364da2661108https://community.developer.atlassian.com/t/action-required-atlassian-connect-vulnerability-allows-bypass-of-app-qsh-verification-via-context-jwts/47072Vendor Advisory
af854a3a-2127-422b-91ae-364da2661108https://confluence.atlassian.com/pages/viewpage.action?pageId=1051986106Vendor Advisory
Impacted products
Vendor Product Version
atlassian connect_spring_boot *
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "Atlassian Connect Spring Boot (ACSB)",
          "vendor": "Atlassian",
          "versions": [
            {
              "lessThan": "unspecified",
              "status": "affected",
              "version": "1.1.0",
              "versionType": "custom"
            },
            {
              "lessThan": "2.1.3",
              "status": "affected",
              "version": "unspecified",
              "versionType": "custom"
            }
          ]
        }
      ],
      "source": "security@atlassian.com"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:atlassian:connect_spring_boot:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "2AA2CBC2-F9F4-4F3C-8446-D995F1D8AE2E",
              "versionEndExcluding": "2.1.3",
              "versionStartIncluding": "1.1.0",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Broken Authentication in Atlassian Connect Spring Boot (ACSB) from version 1.1.0 before version 2.1.3: Atlassian Connect Spring Boot is a Java Spring Boot package for building Atlassian Connect apps. Authentication between Atlassian products and the Atlassian Connect Spring Boot app occurs with a server-to-server JWT or a context JWT. Atlassian Connect Spring Boot versions from version 1.1.0 before version 2.1.3 erroneously accept context JWTs in lifecycle endpoints (such as installation) where only server-to-server JWTs should be accepted, permitting an attacker to send authenticated re-installation events to an app."
    },
    {
      "lang": "es",
      "value": "Autenticaci\u00f3n rota en Atlassian Connect Spring Boot (ACSB) desde la versi\u00f3n 1.1.0 versiones anteriores a 2.1.3: Atlassian Connect Spring Boot es un paquete Java Spring Boot para crear aplicaciones de Atlassian Connect. La autenticaci\u00f3n entre los productos de Atlassian y la aplicaci\u00f3n Atlassian Connect Spring Boot se produce con un JWT de servidor a servidor o un JWT de contexto. Las versiones de Atlassian Connect Spring Boot desde la versi\u00f3n 1.1.0 versiones anteriores a 2.1.3 aceptan err\u00f3neamente JWTs de contexto en los puntos finales del ciclo de vida (como la instalaci\u00f3n) cuando solo deber\u00edan aceptarse JWTs de servidor a servidor, lo que permite a un atacante enviar eventos de reinstalaci\u00f3n autenticados a una aplicaci\u00f3n"
    }
  ],
  "id": "CVE-2021-26074",
  "lastModified": "2026-06-17T03:42:48.300",
  "metrics": {
    "cvssMetricV2": [
      {
        "acInsufInfo": false,
        "baseSeverity": "MEDIUM",
        "cvssData": {
          "accessComplexity": "LOW",
          "accessVector": "NETWORK",
          "authentication": "SINGLE",
          "availabilityImpact": "NONE",
          "baseScore": 4.0,
          "confidentialityImpact": "NONE",
          "integrityImpact": "PARTIAL",
          "vectorString": "AV:N/AC:L/Au:S/C:N/I:P/A:N",
          "version": "2.0"
        },
        "exploitabilityScore": 8.0,
        "impactScore": 2.9,
        "obtainAllPrivilege": false,
        "obtainOtherPrivilege": false,
        "obtainUserPrivilege": false,
        "source": "nvd@nist.gov",
        "type": "Primary",
        "userInteractionRequired": false
      }
    ],
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 6.5,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 3.6,
        "source": "nvd@nist.gov",
        "type": "Primary"
      },
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 6.5,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 3.6,
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2021-26074",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2025-02-12T20:51:32.887613Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2021-04-16T03:15:12.113",
  "references": [
    {
      "source": "security@atlassian.com",
      "tags": [
        "Vendor Advisory"
      ],
      "url": "https://community.developer.atlassian.com/t/action-required-atlassian-connect-vulnerability-allows-bypass-of-app-qsh-verification-via-context-jwts/47072"
    },
    {
      "source": "security@atlassian.com",
      "tags": [
        "Vendor Advisory"
      ],
      "url": "https://confluence.atlassian.com/pages/viewpage.action?pageId=1051986106"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Vendor Advisory"
      ],
      "url": "https://community.developer.atlassian.com/t/action-required-atlassian-connect-vulnerability-allows-bypass-of-app-qsh-verification-via-context-jwts/47072"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Vendor Advisory"
      ],
      "url": "https://confluence.atlassian.com/pages/viewpage.action?pageId=1051986106"
    }
  ],
  "sourceIdentifier": "security@atlassian.com",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-287"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    },
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-287"
        }
      ],
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "type": "Secondary"
    }
  ]
}



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