# CVE-2026-126165: CVE-2026-126165

Status: published. Published: 2026-11-11. Updated: 2026-11-11.

A memory allocation with excessive size value 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 a remote unauthenticated attacker to cause a denial of service via a specially crafted attachment delivered over SMTP.

## Remediation

- fix: Upgrade to FortiMail version 8.0.2 or above
Upgrade to FortiMail version 7.6.7 or above
Upgrade to FortiMail version 7.4.9 or above (source: CNA: fortinet)

## Affected products and versions

- Fortinet / FortiMail: ≥ 8.0.0; ≤ 8.0.1 (affected, semver); ≥ 7.6.0; ≤ 7.6.6 (affected, semver); ≥ 7.4.0; ≤ 7.4.8 (affected, semver); ≥ 7.2.0; ≤ 7.2.9 (affected, semver); ≥ 7.0.0; ≤ 7.0.9 (affected, semver). Source: CNA: fortinet

## Severity and prioritization

- CVSS 3.1: 7.5 (high); CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:P/RL:O/RC:C; source: CNA: fortinet

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: Not available

- Weaknesses: CWE-789

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://fortiguard.fortinet.com/psirt/FG-IR-26-217 (CNA: fortinet)

## Provenance

- CNA: fortinet: https://www.cve.org/CVERecord?id=CVE-2026-126165; retrieved 2026-11-11; source updated 2026-11-11

Revision: 90a9542ab25f6b34c71c452699a58d583e5f23dce569c63a23894abb081284f9

Canonical: https://y2.dev/cve/CVE-2026-126165

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