CVE-2022-39958: Response body bypass in OWASP ModSecurity Core Rule Set via repeated HTTP Range header submission with a small byte range

Published Sep 20, 2022
·
Updated

The OWASP ModSecurity Core Rule Set (CRS) is affected by a response body bypass to sequentially exfiltrate small and undetectable sections of data by repeatedly submitting an HTTP Range header field with a small byte range. A restricted resource, access to which would ordinarily be detected, may be exfiltrated from the backend, despite being protected by a web application firewall that uses CRS. Short subsections of a restricted resource may bypass pattern matching techniques and allow undetected access. The legacy CRS versions 3.0.x and 3.1.x are affected, as well as the currently supported versions 3.2.1 and 3.3.2. Integrators and users are advised to upgrade to 3.2.2 and 3.3.3 respectively and to configure a CRS paranoia level of 3 or higher.

Affected Software

6 affected components
OWASP OWASP ModSecurity Core Rule Set>=3.0.0<3.2.2
OWASP OWASP ModSecurity Core Rule Set>=3.3.0<3.3.3
Fedoraproject Fedora=35
Fedoraproject Fedora=36
Fedoraproject Fedora=37
Debian Debian Linux=10.0

Remediation

Information

upgrade to 3.2.2 or 3.3.3 and configure a CRS paranoia level of 3 or higher.

Event History

Sep 20, 2022
CVE Published
via MITRE·12:00 AM
Data Sourced
via MITRE·12:00 AM
RemedyDescriptionSeverityWeakness
Data Sourced
via NVD·07:15 AM
RemedyDescriptionSeverityWeaknessAffected Software
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Frequently Asked Questions

1

What is CVE-2022-39958?

CVE-2022-39958 is a vulnerability in the OWASP ModSecurity Core Rule Set (CRS) that allows for the sequential exfiltration of small and undetectable sections of data.

2

How does CVE-2022-39958 work?

CVE-2022-39958 works by repeatedly submitting an HTTP Range header field with a small byte range, bypassing the response body and allowing for data exfiltration.

3

Which software is affected by CVE-2022-39958?

The OWASP ModSecurity Core Rule Set (CRS) versions 3.0.0 to 3.2.2 and versions 3.3.0 to 3.3.3 are affected by CVE-2022-39958. Additionally, Fedora versions 35, 36, and 37, as well as Debian Linux 10.0, are also affected.

4

What is the severity of CVE-2022-39958?

CVE-2022-39958 has a severity score of 7.5, indicating a high level of vulnerability.

5

How can CVE-2022-39958 be fixed?

To fix CVE-2022-39958, it is recommended to update to the latest versions of the OWASP ModSecurity Core Rule Set (CRS) or apply the necessary patches provided by the software vendor.

Contact

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