SB2021081816 - Multiple vulnerabilities in HAProxy

CSH
CYBERSECURITY HELP
Sign In REGISTER

Main Vulnerability Database SB2021081816

SB2021081816 - Multiple vulnerabilities in HAProxy

Published: August 18, 2021

Security Bulletin ID SB2021081816
Severity
Medium
Patch available
YES
Number of vulnerabilities 3
Exploitation vector Remote access
Highest impact Data manipulation

Breakdown by Severity

Medium 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 3 secuirty vulnerabilities.


1) Input validation error (CVE-ID: CVE-2021-39242)

The vulnerability allows a remote attacker to bypass implemented security restrictions.

The vulnerability exists due to insufficient validation of user-supplied input when processing HTTP headers. A remote attacker can send a specially crafted Host header to the application and bypass implemented security restrictions.


2) Input validation error (CVE-ID: CVE-2021-39241)

The vulnerability allows a remote attacker to bypass implemented security restrictions.

The vulnerability exists due to insufficient validation of user-supplied input in HAProxy.  An HTTP method name may contain a space followed by the name of a protected resource. It is possible that a server would interpret this as a request for that protected resource, such as in the "GET /admin? HTTP/1.1 /static/images HTTP/1.1" example.

The attacker can abuse such behavior to bypass implemented security restrictions and perform unauthorized actions against the web application behind the HAProxy.


3) Input validation error (CVE-ID: CVE-2021-39240)

The vulnerability allows a remote attacker to bypass security restrictions.

The vulnerability exists due to insufficient validation of user-supplied input when processing HTTP/2 requests. HAProxy does not ensure that the scheme and path portions of a URI have the expected characters, e.g. the authority field on a target HTTP/2 server might differ from what the routing rules were intended to achieve. A remote attacker can send specially crafted input to the application and bypass implemented security restrictions.


Remediation

Install update from vendor's website.

References