How severe is CVE-2025-25255?

CVE-2025-25255 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2025-25255 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (32nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-25255?

CVE-2025-25255 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-2025-25255?

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

Does CVE-2025-25255 have an EU (EUVD) identifier?

Yes. CVE-2025-25255 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-34236.

When was CVE-2025-25255 published?

CVE-2025-25255 was published on 2025-10-14 and last updated on 2026-06-17.

CVE-2025-25255

CVE-2025-25255 is a medium-severity vulnerability in Fortinet Fortiproxy with a CVSS 3.x base score of 5.3. 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-358.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
EPSS exploit prediction: 0% (32nd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-34236
Weakness: CWE-358
Affected product: Fortinet Fortiproxy
Published: 2025-10-14
Last modified: 2026-06-17

Description

An Improperly Implemented Security Check for Standard vulnerability [CWE-358] vulnerability in Fortinet FortiOS 7.6.0 through 7.6.3, FortiProxy 7.6.0 through 7.6.3, FortiProxy 7.4.0 through 7.4.11, FortiProxy 7.2 all versions, FortiProxy 7.0.1 through 7.0.22 may allow an unauthenticated proxy user to bypass the domain fronting protection feature via crafted HTTP requests.

Frequently asked questions

What is CVE-2025-25255?: An Improperly Implemented Security Check for Standard vulnerability [CWE-358] vulnerability in Fortinet FortiOS 7.6.0 through 7.6.3, FortiProxy 7.6.0 through 7.6.3, FortiProxy 7.4.0 through 7.4.11, FortiProxy 7.2 all versions, FortiProxy 7.0.1 through 7.0.22 may allow an unauthenticated proxy user to bypass the domain fronting protection feature via crafted HTTP requests.
How severe is CVE-2025-25255?: CVE-2025-25255 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2025-25255 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (32nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-25255?: CVE-2025-25255 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-2025-25255?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-25255 have an EU (EUVD) identifier?: Yes. CVE-2025-25255 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-34236.
When was CVE-2025-25255 published?: CVE-2025-25255 was published on 2025-10-14 and last updated on 2026-06-17.

References

https://fortiguard.fortinet.com/psirt/FG-IR-24-372

Affected products (2)

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

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