How severe is CVE-2025-54365?

CVE-2025-54365 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2025-54365 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (50th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-54365?

CVE-2025-54365 affects Fastapi-guard Fastapi Guard. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-54365?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2025-54365 have an EU (EUVD) identifier?

Yes. CVE-2025-54365 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-22476.

When was CVE-2025-54365 published?

CVE-2025-54365 was published on 2025-07-23 and last updated on 2026-06-17.

CVE-2025-54365

CVE-2025-54365 is a high-severity vulnerability in Fastapi-guard Fastapi Guard with a CVSS 3.x base score of 7.5. 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-1333.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v4: 7.8
EPSS exploit prediction: 1% (50th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-22476
Weakness: CWE-1333
Affected product: Fastapi-guard Fastapi Guard
Published: 2025-07-23
Last modified: 2026-06-17

Description

fastapi-guard is a security library for FastAPI that provides middleware to control IPs, log requests, detect penetration attempts and more. In version 3.0.1, the regular expression patched to mitigate the ReDoS vulnerability by limiting the length of string fails to catch inputs that exceed this limit. This type of patch fails to detect cases in which the string representing the attributes of a <script> tag exceeds 100 characters. As a result, most of the regex patterns present in version 3.0.1 can be bypassed. This is fixed in version 3.0.2.

Frequently asked questions

What is CVE-2025-54365?: fastapi-guard is a security library for FastAPI that provides middleware to control IPs, log requests, detect penetration attempts and more. In version 3.0.1, the regular expression patched to mitigate the ReDoS vulnerability by limiting the length of string fails to catch inputs that exceed this limit. This type of patch fails to detect cases in which the string representing the attributes of a <script> tag exceeds 100 characters. As a result, most of the regex patterns present in version 3.0.1 can be bypassed. This is fixed in version 3.0.2.
How severe is CVE-2025-54365?: CVE-2025-54365 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2025-54365 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (50th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-54365?: CVE-2025-54365 affects Fastapi-guard Fastapi Guard. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-54365?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2025-54365 have an EU (EUVD) identifier?: Yes. CVE-2025-54365 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-22476.
When was CVE-2025-54365 published?: CVE-2025-54365 was published on 2025-07-23 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:fastapi-guard:fastapi_guard:3.0.1:*:*:*:*:*:*:*

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