CVE-2026-116020mediumCWE-863

CVE-2026-116020: medium-severity vulnerability in BookStackApp BookStack

BookStack before 26.09.2 Incorrect Authorization via AttachmentController on Draft Pages

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13Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 5.3epss 0.2%
BookStack before 26.09.2 contains an incorrect authorization vulnerability in AttachmentController that allows authenticated users to access other users' draft page attachments by ID. Attackers with attachment permissions can enumerate sequential attachment IDs to download, rename, relink, or replace files on another user's unpublished draft pages.
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
Affected products
BookStackApp · BookStack
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