{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-76216", "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "state": "PUBLISHED", "assignerShortName": "VulnCheck", "dateReserved": "2026-08-19T11:35:13.689Z", "datePublished": "2026-08-19T14:02:01.282Z", "dateUpdated": "2026-08-19T14:02:01.282Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "shortName": "VulnCheck", "dateUpdated": "2026-08-19T14:02:01.282Z"}, "datePublic": "2026-08-04T00:00:00.000Z", "title": "Vikunja through 2.4.0 Principal-Type Confusion via LinkSharing", "descriptions": [{"lang": "en", "value": "Vikunja through 2.4.0 contains a principal-type confusion vulnerability where LinkSharing principals with id N are treated as user principals with users.id == N at three permission checks lacking type guards. Attackers with a link-share JWT can remove victims from teams, enumerate and delete victim bot users, or read team rosters by exploiting id collisions in the autoincrement space."}], "problemTypes": [{"descriptions": [{"lang": "en", "description": "Authorization Bypass Through User-Controlled Key", "cweId": "CWE-639", "type": "CWE"}]}], "affected": [{"vendor": "go-vikunja", "product": "vikunja", "defaultStatus": "unaffected", "packageURL": "pkg:golang/code.vikunja.io/api", "versions": [{"version": "0", "status": "affected", "versionType": "semver", "lessThanOrEqual": "2.4.0"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:vikunja:vikunja:*:*:*:*:*:*:*:*", "versionEndIncluding": "2.4.0"}]}]}], "metrics": [{"format": "CVSS", "cvssV4_0": {"version": "4.0", "vectorString": "CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N", "attackVector": "NETWORK", "attackComplexity": "HIGH", "attackRequirements": "PRESENT", "privilegesRequired": "LOW", "userInteraction": "NONE", "vulnConfidentialityImpact": "HIGH", "vulnIntegrityImpact": "HIGH", "vulnAvailabilityImpact": "HIGH", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "subAvailabilityImpact": "NONE", "baseScore": 7.7, "baseSeverity": "HIGH"}}, {"format": "CVSS", "cvssV3_1": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H", "attackVector": "NETWORK", "attackComplexity": "HIGH", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH", "baseScore": 7.5, "baseSeverity": "HIGH"}}], "references": [{"url": "https://github.com/go-vikunja/vikunja/security/advisories/GHSA-32r8-5843-4qw2", "tags": ["vendor-advisory"], "name": "GitHub Security Advisory (GHSA-32r8-5843-4qw2)"}, {"name": "VulnCheck Advisory: Vikunja through 2.4.0 Principal-Type Confusion via LinkSharing", "tags": ["third-party-advisory"], "url": "https://www.vulncheck.com/advisories/vikunja-through-principal-type-confusion-via-linksharing"}], "credits": [{"lang": "en", "value": "manus-use", "type": "reporter"}], "x_generator": {"engine": "vulncheck-endgame"}}}}

{}

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{}

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