CVE-2026-84695 (GCVE-0-2026-84695)
Vulnerability from cvelistv5
Published
2026-09-02 00:37
Modified
2026-09-02 16:01
Severity ?
9.3 (Critical) - CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:H/VI:H/VA:N/SC:H/SI:H/SA:N
8.7 (High) - CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Summary
BookStack before 26.05.4 contains a stored cross-site scripting vulnerability in the drawing upload endpoint that accepts unvalidated base64 content and stores it without content inspection. Attackers with editor permissions can upload SVG files containing scripts that execute in administrator browsers when accessed through the image gallery API without content-type validation or CSP headers.
References
Impacted products
Vendor Product Version
bookstackapp bookstack Version: 0   < 26.05.4
Patch: 26.05.4
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