CVE-2026-84695: BookStack before 26.05.4 Stored XSS via Drawing Upload
bookstackapp · bookstack
Fixed in 26.05.4 · Affected: bookstackapp before 26.05.4 · Exploitation: unlikely (under 1%)
Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.
Higher than 41% of scored CVEs
DescriptionCVE.org
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.
Affected products1
From the CVE record. A product or version that is not listed is unknown, not unaffected.
- bookstackapp · bookstackbefore 26.05.4
On the Atlas
Every published CVE is on the CyberSIXT Atlas, grouped by weakness, vendor and month.
- Exploitation
- Unlikely (under 1%). EPSS under 1%, or no score yet.
- CISA KEV
- Not listed
- Public check
- No public nuclei template
- Weakness
- Cross-site Scripting
- Vendor
- bookstackapp
- Published
- September 2026
CoverageNo articles yet
No CyberSIXT article names CVE-2026-84695 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.