CVE-2021-3915: bookstack is vulnerable to Unrestricted Upload of File with Dangerous Type

high Affects ssddanbrown/bookstack. Feed 2026.10.29.1, updated 2026-10-28; published 2021-11-15; advisory modified 2023-11-08.

bookstack is vulnerable to Unrestricted Upload of File with Dangerous Type

Package: ssddanbrown/bookstack Composer
Affected versions: <21.0.3
Fixed in: 21.0.3
Severity: high CVSS 7.6
Exploitation: not on CISA KEV · EPSS 1% (61.5th percentile)
Published: 2021-11-15
Source: osv.dev

References

CWE-434

NVD record ssddanbrown/bookstack advisories

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Related advisories

CVE-2021-4119 medium BookStack is vulnerable to Improper Access Control. same package: ssddanbrown/bookstack
CVE-2020-5256 high Remote Code Execution Through Image Uploads in BookStack same package: ssddanbrown/bookstack
CVE-2020-26211 high Bookstack Cross-site Scripting vulnerability same package: ssddanbrown/bookstack
CVE-2021-4026 medium bookstack is vulnerable to Improper Access Control same package: ssddanbrown/bookstack
CVE-2020-11055 medium Cross-Site Scripting in BookStack same package: ssddanbrown/bookstack
CVE-2022-0877 medium Cross-site Scripting in BookStack same package: ssddanbrown/bookstack