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Vulnerability DatabaseCVE-2021-26691

CVE-2021-26691: 
Apache HTTP Server vulnerability analysis and mitigation

Overview

In Apache HTTP Server versions 2.4.0 to 2.4.46, a specially crafted SessionHeader sent by an origin server could cause a heap overflow. This vulnerability is tracked as CVE-2021-26691 and was discovered internally by Christophe Jaillet (Apache Security, OSS Security).

Technical details

The vulnerability affects the mod_session module in Apache HTTP Server and allows an origin server to trigger a heap overflow through a specially crafted SessionHeader. The issue impacts versions 2.4.0 through 2.4.46 of the Apache HTTP Server. The vulnerability has been assigned a CVSS score indicating critical severity (NetApp Advisory).

Impact

A successful exploitation of this vulnerability could lead to disclosure of sensitive information, addition or modification of data, or Denial of Service (DoS). The vulnerability has been rated as critical with a CVSS v3.1 base score of 9.8, indicating potential for high impact on confidentiality, integrity and availability (NetApp Advisory).

Mitigation and workarounds

Users should upgrade to Apache HTTP Server version 2.4.48 or later which contains the fix for this vulnerability. Multiple Linux distributions have also released security updates including Debian (DSA-4937-1), Fedora, and Gentoo to address this issue (Debian Security, Gentoo Security).

Additional resources

Source: This report was generated using AI

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