What is CVE-2026-59837?

CVE-2026-59837 is a medium-severity vulnerability in Fortinet Fortios, classified under Stack-based Buffer Overflow. CVSS score: 6.6/10. Published 2026-07-14.

How severe is CVE-2026-59837?

Medium severity. CVSS v3 base score is 6.6 out of 10.

Buffer overflow in Fortinet Fortios

CVE-2026-59837

A stack-based buffer overflow vulnerability in Fortinet FortiOS 7.4.0 through 7.4.1, FortiOS 7.2 all versions, FortiPAM 1.8.0 through 1.8.2, FortiPAM 1.7 all versions, FortiPAM 1.6 all versions, FortiPAM 1.5 all versions, FortiPAM 1.4 all versions, FortiPAM 1.3 all versions, FortiPAM 1.2 all versions, FortiPAM 1.1 all versions, FortiPAM 1.0 all versions, FortiProxy 7.4.0 through 7.4.13, FortiProxy 7.2 all versions may allow a privileged authenticated attacker who can bypass stack protection and ASLR to execute arbitrary code or commands via crafted HTTP requests.

Vulnerability class: Buffer Overflow

EPSS: 0.007 (49.4th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.6 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H.

Affected products

Fortinet Fortios — versions 7.4.0, 7.2.0, 7.0.0
Fortinet Fortipam — versions 1.8.0, 1.7.0, 1.6.0
Fortinet Fortiproxy — versions 7.4.0, 7.2.0
Fortinet Fortisase — versions 26.1.1

Weakness classification (CWE)

CWE-121 — Stack-based Buffer Overflow

References

psirt@fortinet.com (Vendor Advisory)
0b142b55-0307-4c5a-b3c9-f314f3fb7c5e

Frequently asked questions

What is CVE-2026-59837?: CVE-2026-59837 is a medium-severity vulnerability in Fortinet Fortios, classified under Stack-based Buffer Overflow. CVSS score: 6.6/10. Published 2026-07-14.
How severe is CVE-2026-59837?: Medium severity. CVSS v3 base score is 6.6 out of 10.