CVE-2021-3906 json
Unrestricted Upload of File with Dangerous Type in bookstackapp/bookstack
published 2021-10-27 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-27134
- cvss
- 5.4
- version 3.0, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.7%
- EPSS 0.7% chance of exploitation in 30 days, percentile 52%
- public exploits
- 0
- none known
Summary
bookstack is vulnerable to Unrestricted Upload of File with Dangerous Type
Patch / fix
- bookstackapp bookstackapp/bookstack 21.10.1
Exploit prediction
0.67% chance of exploitation in the next 30 days, higher than 52% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- huntr.dev https://huntr.dev/bounties/f115bdf5-c06b-4627-a6fa-ba6904a43ba3 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.0 | 5.4 | CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N |
| NVD | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N |
| NVD | 2.0 | 4.0 | AV:N/AC:L/Au:S/C:P/I:N/A:N |
Affected products
- bookstackapp bookstackapp/bookstack
Classification
- Weakness
-
- CWE-434 Unrestricted Upload of File with Dangerous Type
References
-
github.com
/bookstackapp/bookstack/commit/64937ab826b56d086af9ecea532510d37520ebc8
patch, third-party-advisory
-
huntr.dev
/bounties/f115bdf5-c06b-4627-a6fa-ba6904a43ba3
exploit, issue-tracking, patch, third-party-advisory
Sources
- CVE List CVE-2021-3906
- NVD CVE-2021-3906
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