CVE-2025-47947

Description

ModSecurity is an open source, cross platform web application firewall (WAF) engine for Apache, IIS and Nginx. Versions up to and including 2.9.8 are vulnerable to denial of service in one special case (in stable released versions): when the payload's content type is `application/json`, and there is at least one rule which does a `sanitiseMatchedBytes` action. A patch is available at pull request 3389 and expected to be part of version 2.9.9. No known workarounds are available.

How to fix CVE-2025-47947

To remediate CVE-2025-47947, upgrade the affected package to a fixed version below.

—upgrade to 3.0.12 or later
—upgrade to 2.9.9 or later
—upgrade to 2.9.3-3+deb11u3 or later
—upgrade to 2.9.3-3+deb11u3 or later
—upgrade to 2.9.7-1+deb12u1 or later

Is CVE-2025-47947 being exploited?

Low — EPSS is 0.6%, meaning exploitation activity has not been observed at scale.

Affected packages (5)

from 0, < 3.0.12
from 0, < 2.9.9
from 0, < 2.9.3-3+deb11u3
from 0, < 2.9.3-3+deb11u3
from 0, < 2.9.7-1+deb12u1

CVSS scores

Source	Version	Severity	Vector
osv	CVSS 3.1	HIGH7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H