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 6.2.0 through 6.2.7 may allow an unauthenticated attacker to infer parts…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.31%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
- EPSS
- 0.31% probability · 23th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-338
- Affected
- fortinet/fortimail
- Source
- psirt@fortinet.com
EPSS 0.3% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://fortiguard.com/advisory/FG-IR-21-031Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.