How severe is CVE-2025-52891?

CVE-2025-52891 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2025-52891 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (27th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2025-52891?

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

Does CVE-2025-52891 have an EU (EUVD) identifier?

Yes. CVE-2025-52891 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-19726.

When was CVE-2025-52891 published?

CVE-2025-52891 was published on 2025-07-02 and last updated on 2026-06-17.

CVE-2025-52891

CVE-2025-52891 is a medium-severity vulnerability with a CVSS 3.x base score of 6.5. 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-20.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
EPSS exploit prediction: 0% (27th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-19726
Weakness: CWE-20
Published: 2025-07-02
Last modified: 2026-06-17

Description

ModSecurity is an open source, cross platform web application firewall (WAF) engine for Apache, IIS and Nginx. In versions 2.9.8 to before 2.9.11, an empty XML tag can cause a segmentation fault. If SecParseXmlIntoArgs is set to On or OnlyArgs, and the request type is application/xml, and at least one XML tag is empty (eg <foo></foo>), then a segmentation fault occurs. This issue has been patched in version 2.9.11. A workaround involves setting SecParseXmlIntoArgs to Off.

Frequently asked questions

What is CVE-2025-52891?: ModSecurity is an open source, cross platform web application firewall (WAF) engine for Apache, IIS and Nginx. In versions 2.9.8 to before 2.9.11, an empty XML tag can cause a segmentation fault. If SecParseXmlIntoArgs is set to On or OnlyArgs, and the request type is application/xml, and at least one XML tag is empty (eg <foo></foo>), then a segmentation fault occurs. This issue has been patched in version 2.9.11. A workaround involves setting SecParseXmlIntoArgs to Off.
How severe is CVE-2025-52891?: CVE-2025-52891 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2025-52891 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (27th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2025-52891?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-52891 have an EU (EUVD) identifier?: Yes. CVE-2025-52891 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-19726.
When was CVE-2025-52891 published?: CVE-2025-52891 was published on 2025-07-02 and last updated on 2026-06-17.

References

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