Medium severity · published Nov 5, 2021
CVE-2021-3916
bookstack is vulnerable to Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
6.5
CVSS
1.2%
EPSS
No
On KEV
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.2% · higher than 69% 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-2021-3916
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-3916
Patch
https://github.com/bookstackapp/bookstack/commit/43830a372fc51a8793199d04a34c3f4ebdfccc7b
Exploit
https://huntr.dev/bounties/0be32e6b-7c48-43f0-9cec-433000ad8f64
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