How severe is CVE-2025-48866?

CVE-2025-48866 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-2025-48866 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-2025-48866?

CVE-2025-48866 affects Owasp Modsecurity. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-48866?

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-2025-48866 have an EU (EUVD) identifier?

Yes. CVE-2025-48866 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-16670.

When was CVE-2025-48866 published?

CVE-2025-48866 was published on 2025-06-02 and last updated on 2026-06-17.

CVE-2025-48866

CVE-2025-48866 is a high-severity vulnerability in Owasp Modsecurity 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-1050.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (51st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-16670
Weakness: CWE-1050
Affected product: Owasp Modsecurity
Published: 2025-06-02
Last modified: 2026-06-17

Description

ModSecurity is an open source, cross platform web application firewall (WAF) engine for Apache, IIS and Nginx. Versions prior to 2.9.10 contain a denial of service vulnerability similar to GHSA-859r-vvv8-rm8r/CVE-2025-47947. The `sanitiseArg` (and `sanitizeArg` - this is the same action but an alias) is vulnerable to adding an excessive number of arguments, thereby leading to denial of service. Version 2.9.10 fixes the issue. As a workaround, avoid using rules that contain the `sanitiseArg` (or `sanitizeArg`) action.

Frequently asked questions

What is CVE-2025-48866?: ModSecurity is an open source, cross platform web application firewall (WAF) engine for Apache, IIS and Nginx. Versions prior to 2.9.10 contain a denial of service vulnerability similar to GHSA-859r-vvv8-rm8r/CVE-2025-47947. The `sanitiseArg` (and `sanitizeArg` - this is the same action but an alias) is vulnerable to adding an excessive number of arguments, thereby leading to denial of service. Version 2.9.10 fixes the issue. As a workaround, avoid using rules that contain the `sanitiseArg` (or `sanitizeArg`) action.
How severe is CVE-2025-48866?: CVE-2025-48866 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-2025-48866 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-2025-48866?: CVE-2025-48866 affects Owasp Modsecurity. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-48866?: 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-2025-48866 have an EU (EUVD) identifier?: Yes. CVE-2025-48866 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-16670.
When was CVE-2025-48866 published?: CVE-2025-48866 was published on 2025-06-02 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:owasp:modsecurity:*:*:*:*:*:*:*:*

More vulnerabilities in Owasp Modsecurity

CVE-2024-1019 — High (CVSS 8.6): ModSecurity / libModSecurity 3.0.0 to 3.0.11 is affected by a WAF bypass for path-based payloads submitted via…
CVE-2026-42268 — High (CVSS 7.5): ModSecurity is an open source, cross platform web application firewall (WAF) engine for Apache, IIS and Nginx. From…
CVE-2026-30923 — High (CVSS 7.5): ModSecurity is an open source, cross platform web application firewall (WAF) engine for Apache, IIS and Nginx.…
CVE-2023-38285 — High (CVSS 7.5): Trustwave ModSecurity 3.x before 3.0.10 has Inefficient Algorithmic Complexity.
CVE-2023-28882 — High (CVSS 7.5): Trustwave ModSecurity 3.0.5 through 3.0.8 before 3.0.9 allows a denial of service (worker crash and unresponsiveness)…
CVE-2022-48279 — High (CVSS 7.5): In ModSecurity before 2.9.6 and 3.x before 3.0.8, HTTP multipart requests were incorrectly parsed and could bypass the…

All CVEs affecting Owasp Modsecurity →

Other CWE-1050 vulnerabilities

CVE-2026-4634 — High (CVSS 7.5): A flaw was found in Keycloak. An unauthenticated attacker can exploit this vulnerability by sending a specially crafted…
CVE-2025-67419 — High (CVSS 7.5): A Denial of Service (DoS) vulnerability in evershop 2.1.0 and prior allows unauthenticated attackers to exhaust the…
CVE-2025-47947 — High (CVSS 7.5): ModSecurity is an open source, cross platform web application firewall (WAF) engine for Apache, IIS and Nginx. Versions…
CVE-2024-4068 — High (CVSS 7.5): The NPM package `braces`, versions prior to 3.0.3, fails to limit the number of characters it can handle, which could…
CVE-2023-1390 — High (CVSS 7.5): A remote denial of service vulnerability was found in the Linux kernel’s TIPC kernel module. The while loop in…
CVE-2021-41039 — High (CVSS 7.5): In versions 1.6 to 2.0.11 of Eclipse Mosquitto, an MQTT v5 client connecting with a large number of user-property…

Browse all CWE-1050 vulnerabilities →