CVE-2026-123527 (GCVE-0-2026-123527)

Vulnerability from cvelistv5 – Published: 2026-11-08 01:37 – Updated: 2026-11-08 01:37
VLAI
Title
Vikunja 2.4.0 before 2.7.1 API Token Scope Collision Authorization Bypass
Summary
Vikunja from 2.4.0 before 2.7.1 contains an authorization bypass vulnerability that allows token holders to perform unintended operations due to colliding v1 and v2 API token permission keys. Attackers with a token scoped to read project backgrounds can delete them via the v2 DELETE background route, and bucket create-only tokens can update existing buckets.
Severity
5.3 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N
5.4 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L
CWE
  • CWE-863 - Incorrect Authorization
Assigner
VulnCheck CNA
References
Impacted products
Vendor Product Version
go-vikunja vikunja Affected: 2.4.0 , < 2.7.1 (semver)
Unaffected: 2.7.1 (semver)
    cpe:2.3:a:vikunja:vikunja:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-10-22 00:00
Credits
dylanzonix
Show details on NVD website
To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "packageURL": "pkg:golang/code.vikunja.io/api",
          "product": "vikunja",
          "vendor": "go-vikunja",
          "versions": [
            {
              "lessThan": "2.7.1",
              "status": "affected",
              "version": "2.4.0",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "2.7.1",
              "versionType": "semver"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:a:vikunja:vikunja:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "2.7.1",
                  "versionStartIncluding": "2.4.0",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "reporter",
          "value": "dylanzonix"
        }
      ],
      "datePublic": "2026-10-22T00:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "value": "Vikunja from 2.4.0 before 2.7.1 contains an authorization bypass vulnerability that allows token holders to perform unintended operations due to colliding v1 and v2 API token permission keys. Attackers with a token scoped to read project backgrounds can delete them via the v2 DELETE background route, and bucket create-only tokens can update existing buckets."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "NETWORK",
            "baseScore": 5.3,
            "baseSeverity": "MEDIUM",
            "privilegesRequired": "LOW",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "LOW",
            "vulnConfidentialityImpact": "NONE",
            "vulnIntegrityImpact": "LOW"
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            "baseScore": 5.4,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "NONE",
            "integrityImpact": "LOW",
            "privilegesRequired": "LOW",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L",
            "version": "3.1"
          },
          "format": "CVSS"
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-863",
              "description": "Incorrect Authorization",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-11-08T01:37:36.283Z",
        "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
        "shortName": "VulnCheck"
      },
      "references": [
        {
          "name": "GitHub Security Advisory (GHSA-j5v7-qcwp-5g32)",
          "tags": [
            "vendor-advisory"
          ],
          "url": "https://github.com/go-vikunja/vikunja/security/advisories/GHSA-j5v7-qcwp-5g32"
        },
        {
          "name": "VulnCheck Advisory: Vikunja 2.4.0 before 2.7.1 API Token Scope Collision Authorization Bypass",
          "tags": [
            "third-party-advisory"
          ],
          "url": "https://www.vulncheck.com/advisories/vikunja-2.4.0-before-2.7.1-api-token-scope-collision-authorization-bypass"
        }
      ],
      "title": "Vikunja 2.4.0 before 2.7.1 API Token Scope Collision Authorization Bypass",
      "x_generator": {
        "engine": "vulncheck-endgame"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
    "assignerShortName": "VulnCheck",
    "cveId": "CVE-2026-123527",
    "datePublished": "2026-11-08T01:37:36.283Z",
    "dateReserved": "2026-11-06T00:48:01.381Z",
    "dateUpdated": "2026-11-08T01:37:36.283Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}



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