How severe is CVE-2026-59837?

CVE-2026-59837 has a CVSS 3.x base score of 6.6, rated medium severity. It is exploitable over network with high attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-59837 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-59837?

CVE-2026-59837 primarily affects Fortinet Fortiproxy. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-59837?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2026-59837 published?

CVE-2026-59837 was published on 2026-07-14 and last updated on 2026-08-11.

CVE-2026-59837

CVE-2026-59837 is a medium-severity vulnerability in Fortinet Fortiproxy with a CVSS 3.x base score of 6.6. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-121.

Key facts

Severity: Medium (CVSS 3.x base score 6.6)
EPSS exploit prediction: 1% (51st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-121
Affected product: Fortinet Fortiproxy
Published: 2026-07-14
Last modified: 2026-08-11

Description

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.

Frequently asked questions

What is 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.
How severe is CVE-2026-59837?: CVE-2026-59837 has a CVSS 3.x base score of 6.6, rated medium severity. It is exploitable over network with high attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-59837 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-59837?: CVE-2026-59837 primarily affects Fortinet Fortiproxy. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-59837?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2026-59837 published?: CVE-2026-59837 was published on 2026-07-14 and last updated on 2026-08-11.

References

Affected products (3)

cpe:2.3:a:fortinet:fortiproxy:*:*:*:*:*:*:*:*
cpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:*
cpe:2.3:o:fortinet:fortipam:*:*:*:*:*:*:*:*

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