CVE-2026-126151 (CVSS 7.5)

Description

A incorrect implementation of authentication algorithm vulnerability in Fortinet FortiMail 8.0.0 through 8.0.1, FortiMail 7.6.0 through 7.6.6, FortiMail 7.4.0 through 7.4.8, FortiMail 7.2 all versions may allow an unauthenticated remote attacker to gain elevation of privilege (account takeover) via a crafted request.

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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

EPSS — Exploit Prediction

0.0058

Probability of exploitation

0.48%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-303 CWE-303

References

Other References

https://fortiguard.fortinet.com/psirt/FG-IR-26-203

Frequently Asked Questions

What is CVE-2026-126151? +

A incorrect implementation of authentication algorithm vulnerability in Fortinet FortiMail 8.0.0 through 8.0.1, FortiMail 7.6.0 through 7.6.6, FortiMail 7.4.0 through 7.4.8, FortiMail 7.2 all versions may allow an unauthenticated remote attacker to gain elevation of privilege (account takeover) via a crafted request. It has a CVSS v3.1 base score of 7.5 (HIGH).

How severe is CVE-2026-126151? +

CVE-2026-126151 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. The EPSS score is 0.0058, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-126151? +

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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