Medium severity · published Nov 13, 2021
CVE-2021-3915
bookstack is vulnerable to Unrestricted Upload of File with Dangerous Type
5.7
CVSS
1%
EPSS
No
On KEV
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
Required
Confidentiality
High
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.0% · higher than 61% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
BO
Bookstack · Bookstackapp
before 21.10.3 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-3915
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-3915
Patch
https://github.com/bookstackapp/bookstack/commit/ae155d67454d6b9f6c93b2bb457aaa4b2eb1a9ed
Exploit
https://huntr.dev/bounties/fcb65f2d-257a-46f4-bac9-f6ded5649079
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