High severity · published Mar 24, 2025
CVE-2021-26091
A use of a cryptographically weak pseudo-random number generator vulnerability in the authenticator of the Identity Based Encryption service of FortiMail 6.4.0 through 6.4.4, and…
7.5
CVSS
0.3%
EPSS
No
On KEV
Description
A use of a cryptographically weak pseudo-random number generator vulnerability in the authenticator of the Identity Based Encryption service of FortiMail 6.4.0 through 6.4.4, and 6.2.0 through 6.2.7 may allow an unauthenticated attacker to infer parts of users authentication tokens and reset their credentials.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 23% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FO
Fortimail · Fortinet
6.2.0 before 6.4.5 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-26091
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-26091
Vendor Advisory
https://fortiguard.com/advisory/FG-IR-21-031
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