SB2021111083 - Red Hat Enterprise Linux 8 update for the httpd:2.4 module



SB2021111083 - Red Hat Enterprise Linux 8 update for the httpd:2.4 module

Published: November 10, 2021

Security Bulletin ID SB2021111083
Severity
High
Patch available
YES
Number of vulnerabilities 3
Exploitation vector Remote access
Highest impact Data manipulation

Breakdown by Severity

High 67% Low 33%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 3 secuirty vulnerabilities.


1) Buffer overflow (CVE-ID: CVE-2021-20325)

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to missing fixes for CVE-2021-40438 and CVE-2021-26691 in the versions of httpd. A remote attacker can trigger memory corruption and execute arbitrary code on the target system.


2) Server-Side Request Forgery (SSRF) (CVE-ID: CVE-2021-40438)

The disclosed vulnerability allows a remote attacker to perform SSRF attacks.

The vulnerability exists due to insufficient validation of user-supplied input within the mod_proxy module in Apache HTTP Server. A remote attacker can send a specially crafted HTTP request with a chosen uri-path and trick the web server to initiate requests to arbitrary systems.

Successful exploitation of this vulnerability may allow a remote attacker gain access to sensitive data, located in the local network or send malicious requests to other servers from the vulnerable system.


3) NULL pointer dereference (CVE-ID: CVE-2021-26691)

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to a NULL pointer dereference error in mod_session. A a malicious backend server or SessionHeader can trigger a denial of service (DoS) condition.


Remediation

Install update from vendor's website.