High severity · published Nov 29, 2025
CVE-2025-53939
Kiteworks Core is vulnerable to Improper Input Validation
8.8
CVSS
0.7%
EPSS
No
On KEV
Description
Kiteworks is a private data network (PDN). Prior to version 9.1.0, improper input validation when managing roles of a shared folder could lead to unexpectedly elevate another user's permissions on the share. This issue has been patched in version 9.1.0.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.7% · higher than 54% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
SE
security-advisories · kiteworks
< 9.1.0 · source: vendor
KI
Kiteworks · Accellion
before 9.1.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-53939
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-53939
Patch
https://github.com/kiteworks/security-advisories/security/advisories/GHSA-hpf5-6376-2565
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