CVE-2021-26091: fortimail Weak RNG — Fix

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.

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CVSS v3.1 Score

7.5

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Weakness Type (CWE)

CWE-338 CWE-338

Affected Products

Vendor	Product	Versions
fortinet	fortimail	6.2.0 — 6.4.5

References

Advisories & Patches

https://fortiguard.com/advisory/FG-IR-21-031

Frequently Asked Questions

What is 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 of users authentication tokens and reset their credentials. It has a CVSS v3.1 base score of 7.5 (HIGH).

How severe is CVE-2021-26091? +

CVE-2021-26091 has a CVSS v3.1 score of 7.5 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

What products are affected by CVE-2021-26091? +

CVE-2021-26091 affects products from fortinet, specifically: fortimail. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2021-26091? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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