{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-86112", "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "state": "PUBLISHED", "assignerShortName": "VulnCheck", "dateReserved": "2026-09-05T01:59:19.567Z", "datePublished": "2026-09-05T09:59:04.004Z", "dateUpdated": "2026-09-05T09:59:04.004Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "shortName": "VulnCheck", "dateUpdated": "2026-09-05T09:59:04.004Z"}, "datePublic": "2026-09-04T00:00:00.000Z", "title": "BookWyrm through 0.9.1 Missing Authorization on the Favorite and Unfavorite Endpoints", "descriptions": [{"lang": "en", "value": "BookWyrm through 0.9.1 fails to validate user visibility permissions in the Favorite and Unfavorite views, allowing authenticated attackers to favorite or unfavorite followers-only and direct statuses they cannot access. Attackers can POST to the favorite endpoint with a status ID to create unauthorized interactions, trigger ActivityPub broadcasts, and enumerate private status IDs through response differentiation."}], "problemTypes": [{"descriptions": [{"lang": "en", "description": "Authorization Bypass Through User-Controlled Key", "cweId": "CWE-639", "type": "CWE"}]}], "affected": [{"vendor": "bookwyrm-social", "product": "bookwyrm", "repo": "https://github.com/bookwyrm-social/bookwyrm", "defaultStatus": "unaffected", "packageURL": "pkg:github/bookwyrm-social/bookwyrm", "versions": [{"version": "0", "lessThanOrEqual": "0.9.1", "status": "affected", "versionType": "semver"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:joinbookwyrm:bookwyrm:*:*:*:*:*:*:*:*", "versionEndIncluding": "0.9.1"}]}]}], "metrics": [{"format": "CVSS", "cvssV4_0": {"version": "4.0", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N", "attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "LOW", "userInteraction": "NONE", "vulnConfidentialityImpact": "LOW", "vulnIntegrityImpact": "LOW", "vulnAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "subAvailabilityImpact": "NONE", "baseScore": 5.3, "baseSeverity": "MEDIUM"}}, {"format": "CVSS", "cvssV3_1": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "availabilityImpact": "NONE", "baseScore": 5.4, "baseSeverity": "MEDIUM"}}], "references": [{"url": "https://github.com/geo-chen/oss/blob/main/bookwyrm.md#finding-2-authenticated-idor-in-favoriteunfavorite-allows-interaction-with-private-statuses", "tags": ["technical-description"], "name": "Researcher write-up: finding 2"}, {"url": "https://github.com/bookwyrm-social/bookwyrm/blob/v0.9.1/bookwyrm/views/interaction.py", "tags": ["technical-description"], "name": "Favorite/Unfavorite fetch by id with no visibility check"}, {"url": "https://github.com/bookwyrm-social/bookwyrm", "tags": ["product"]}, {"name": "VulnCheck Advisory: BookWyrm through 0.9.1 Missing Authorization on the Favorite and Unfavorite Endpoints", "tags": ["third-party-advisory"], "url": "https://www.vulncheck.com/advisories/bookwyrm-through-0.9.1-missing-authorization-on-the-favorite-and-unfavorite-endpoints"}], "credits": [{"lang": "en", "value": "George Chen", "type": "reporter"}], "x_generator": {"engine": "vulncheck-endgame"}}}}

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