CVE-2026-86112

medium

BookWyrm through 0.9.1 fails to validate user visibility permissions in the Favorite and Unfavorite views, allowing authenticated attackers to favorite or unfa…

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.

CVSS

5.4

5.4 (CVSS v3.1)

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

Severity source: NVD CVSS v3.1 (disclosure@vulncheck.com)

Timeline (UTC)

Published: 2026-09-05 10:16

Modified: 2026-09-10 16:18

NVD status: Deferred

Last synced 1 day ago

Verified against the source API 2026-10-27 06:50 UTC

Exploitation

Not listed in CISA KEV (as of last catalog sync)

Absence from KEV does not mean a CVE is not exploited. Exploitation status: unknown (no authoritative evidence in our sources).

Affected products

Not reported by the source (unknown — not "none").

Weakness classification (CWE)

CWE-639

Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.

Mitigation & advisories

No vendor advisory or patch reference tagged by NVD. Check the references below.

References

https://github.com/bookwyrm-social/bookwyrm disclosure@vulncheck.com
https://github.com/bookwyrm-social/bookwyrm/blob/v0.9.1/bookwyrm/views/interaction.py disclosure@vulncheck.com
https://github.com/geo-chen/oss/blob/main/bookwyrm.md#finding-2-authenticated-idor-in-favo... disclosure@vulncheck.com
https://www.vulncheck.com/advisories/bookwyrm-through-0.9.1-missing-authorization-on-the-f... disclosure@vulncheck.com

Data sources

NVD CVE API 2.0 — fetched 2026-10-27 06:50 UTC · record ↗

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