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.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Attack Requirements
None
No additional conditions
Privileges Required
Low
Basic privileges needed
User Interaction
Passive
Minimal interaction
Impact Assessment
Confidentiality
High
Complete data leak
Integrity
High
Complete data modification
Availability
None
No disruption
CVSS Vector v4.0
Weakness Type (CWE)
Vulnerable Products 1
| Configuration | From (including) | Up to (excluding) |
|---|---|---|
|
Bookstackapp Bookstack
cpe:2.3:a:bookstackapp:bookstack:*:*:*:*:*:*:*:*
|
— |
26.05.4
|
References 6
https://github.com/BookStackApp/BookStack
disclosure@vulncheck.com
https://github.com/BookStackApp/BookStack/blob/v26.05.3/app/Uploads/ImageServic…
disclosure@vulncheck.com
https://github.com/BookStackApp/BookStack/commit/ac0348a79f3ddd004ca87703948cb9…
disclosure@vulncheck.com
https://github.com/BookStackApp/BookStack/releases/tag/v26.05.4
disclosure@vulncheck.com
https://www.bookstackapp.com/blog/bookstack-release-v26-05-4/
disclosure@vulncheck.com
https://www.vulncheck.com/advisories/bookstack-before-26.05.4-stored-xss-via-dr…
disclosure@vulncheck.com