Critical severity · published Oct 17, 2025
CVE-2025-56221
A lack of rate limiting in the login mechanism of SigningHub v8.6.8 allows attackers to bypass authentication via a brute force attack
9.8
CVSS
0.6%
EPSS
No
On KEV
Description
A lack of rate limiting in the login mechanism of SigningHub v8.6.8 allows attackers to bypass authentication via a brute force attack.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 48% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
SI
Signinghub · Ascertia
through 8.6.8 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-56221
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-56221
Third Party Advisory
https://github.com/saykino/CVE-2025-56221
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