CVE-2026-126811
mediumBookStack before 26.09.3 contains an incorrect authorization vulnerability that allows authenticated users to access other users' unpublished draft page images…
BookStack before 26.09.3 contains an incorrect authorization vulnerability that allows authenticated users to access other users' unpublished draft page images by checking only PageView permission without draft status. Attackers can read drawio data via the base64 endpoint or rename, replace, or delete draft images by sequential ID to disclose or tamper with unpublished work.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N Affected products
Not reported by the source (unknown — not "none").
Weakness classification (CWE)
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://codeberg.org/bookstack/bookstack/commit/4fec06236cbfb314fd72c1b3614c7c50162fb41c disclosure@vulncheck.com
- https://codeberg.org/bookstack/bookstack/commit/926e16a23f346be47d44746d14cba40cb355cbe1 disclosure@vulncheck.com
- https://codeberg.org/bookstack/bookstack/releases/tag/v26.09.3 disclosure@vulncheck.com
- https://github.com/BookStackApp/BookStack/blob/v26.09.2/app/Uploads/Controllers/DrawioImag... disclosure@vulncheck.com
- https://github.com/BookStackApp/BookStack/blob/v26.09.2/app/Uploads/Controllers/ImageContr... disclosure@vulncheck.com
- https://github.com/BookStackApp/BookStack/commit/926e16a23f346be47d44746d14cba40cb355cbe1 disclosure@vulncheck.com
- https://github.com/BookStackApp/BookStack/releases/tag/v26.09.3 disclosure@vulncheck.com
- https://github.com/fishtankyu/bookstack-draft-image-idor-advisory.md disclosure@vulncheck.com
- https://www.bookstackapp.com/blog/bookstack-release-v26-09-3/ disclosure@vulncheck.com
- https://www.vulncheck.com/advisories/bookstack-before-26.09.3-incorrect-authorization-via-... disclosure@vulncheck.com