How severe is CVE-2026-59840?

CVE-2026-59840 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2026-59840 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (9th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-59840?

CVE-2026-59840 primarily affects Fortinet Fortiproxy. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-59840?

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

When was CVE-2026-59840 published?

CVE-2026-59840 was published on 2026-07-14 and last updated on 2026-08-11.

CVE-2026-59840

CVE-2026-59840 is a medium-severity vulnerability in Fortinet Fortiproxy with a CVSS 3.x base score of 4.3. 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-126.

Key facts

Severity: Medium (CVSS 3.x base score 4.3)
EPSS exploit prediction: 0% (9th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-126
Affected product: Fortinet Fortiproxy
Published: 2026-07-14
Last modified: 2026-08-11

Description

A buffer over-read vulnerability in Fortinet FortiOS 7.6.0 through 7.6.3, FortiOS 7.4.0 through 7.4.8, FortiOS 7.2 all versions, FortiOS 7.0 all versions, FortiOS 6.4 all versions, FortiProxy 7.6.0 through 7.6.5, FortiProxy 7.4.0 through 7.4.13, FortiProxy 7.2 all versions, FortiProxy 7.0 all versions may allow attacker to information disclosure via <insert attack vector here>

Frequently asked questions

What is CVE-2026-59840?: A buffer over-read vulnerability in Fortinet FortiOS 7.6.0 through 7.6.3, FortiOS 7.4.0 through 7.4.8, FortiOS 7.2 all versions, FortiOS 7.0 all versions, FortiOS 6.4 all versions, FortiProxy 7.6.0 through 7.6.5, FortiProxy 7.4.0 through 7.4.13, FortiProxy 7.2 all versions, FortiProxy 7.0 all versions may allow attacker to information disclosure via <insert attack vector here>
How severe is CVE-2026-59840?: CVE-2026-59840 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2026-59840 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (9th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-59840?: CVE-2026-59840 primarily affects Fortinet Fortiproxy. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-59840?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2026-59840 published?: CVE-2026-59840 was published on 2026-07-14 and last updated on 2026-08-11.

References

Affected products (2)

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

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