CVE-2025-48866
ModSecurity SanitizeArg Denial of Service Vulnerability
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.
INFO
Published Date :
June 2, 2025, 4:15 p.m.
Last Modified :
July 2, 2025, 6:11 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | [email protected] |
Solution
- Update ModSecurity to version 2.9.10 or later.
- Avoid rules using the sanitiseArg action if updating is not possible.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2025-48866.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2025-48866 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2025-48866
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2025-48866 vulnerability anywhere in the article.
-
Cyber Security News
Critical ModSecurity WAF Vulnerability Allows Denial of Service via Empty XML Tags
A newly discovered denial-of-service vulnerability in the ModSecurity Web Application Firewall (WAF) engine has security experts on high alert. The flaw, designated CVE-2025-52891, affects specific ve ... Read more
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Cyber Security News
New ModSecurity WAF Vulnerability Let Attackers Crash the System
A significant denial of service vulnerability has been discovered in ModSecurity, one of the most widely deployed open-source web application firewall (WAF) engines used to protect Apache, IIS, and Ng ... Read more
The following table lists the changes that have been made to the
CVE-2025-48866 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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Initial Analysis by [email protected]
Jul. 02, 2025
Action Type Old Value New Value Added CPE Configuration OR *cpe:2.3:a:owasp:modsecurity:*:*:*:*:*:*:*:* versions up to (excluding) 2.9.10 Added Reference Type GitHub, Inc.: https://github.com/owasp-modsecurity/ModSecurity/commit/3a54ccea62d3f7151bb08cb78d60c5e90b53ca2e Types: Patch Added Reference Type GitHub, Inc.: https://github.com/owasp-modsecurity/ModSecurity/security/advisories/GHSA-859r-vvv8-rm8r Types: Not Applicable Added Reference Type GitHub, Inc.: https://github.com/owasp-modsecurity/ModSecurity/security/advisories/GHSA-f82j-8pp7-cw2w Types: Exploit, Vendor Advisory Added Reference Type GitHub, Inc.: https://github.com/owasp-modsecurity/ModSecurity/wiki/Reference-Manual-(v2.x)#sanitisearg Types: Product Added Reference Type CVE: https://lists.debian.org/debian-lts-announce/2025/06/msg00009.html Types: Mailing List -
CVE Modified by af854a3a-2127-422b-91ae-364da2661108
Jun. 09, 2025
Action Type Old Value New Value Added Reference https://lists.debian.org/debian-lts-announce/2025/06/msg00009.html -
New CVE Received by [email protected]
Jun. 02, 2025
Action Type Old Value New Value Added 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. Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Added CWE CWE-1050 Added Reference https://github.com/owasp-modsecurity/ModSecurity/commit/3a54ccea62d3f7151bb08cb78d60c5e90b53ca2e Added Reference https://github.com/owasp-modsecurity/ModSecurity/security/advisories/GHSA-859r-vvv8-rm8r Added Reference https://github.com/owasp-modsecurity/ModSecurity/security/advisories/GHSA-f82j-8pp7-cw2w Added Reference https://github.com/owasp-modsecurity/ModSecurity/wiki/Reference-Manual-(v2.x)#sanitisearg