SB2021071702 - Gentoo update for Apache 



SB2021071702 - Gentoo update for Apache

Published: July 17, 2021

Security Bulletin ID SB2021071702
Severity
Medium
Patch available
YES
Number of vulnerabilities 7
Exploitation vector Remote access
Highest impact Denial of service

Breakdown by Severity

Medium 86% Low 14%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 7 secuirty vulnerabilities.


1) Security restrictions bypass (CVE-ID: CVE-2019-17567)

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

The vulnerability exists due to unspecified error within the mod_proxy_wstunnel and mod_proxy_http modules. If mod_proxy_wstunnel is configured on an URL that is not necessarily Upgraded by the origin server and is tunneling the whole connection regardless, thus allowing for subsequent requests on the same connection to pass through with no HTTP validation, authentication or authorization possibly configured.


2) NULL pointer dereference (CVE-ID: CVE-2020-13950)

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_proxy_http. A remote attacker can pass specially crafted data to the application and perform a denial of service (DoS) attack.


3) Stack-based buffer overflow (CVE-ID: CVE-2020-35452)

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

The vulnerability exists due to a boundary error when processing Digest nounces in mod_auth_digest. A remote unauthenticated attacker can send a specially crafted HTTP request, trigger stack overflow by one nul byte and crash the server.


4) NULL pointer dereference (CVE-ID: CVE-2021-26690)

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 remote attacker can pass specially crafted data to the application and perform a denial of service (DoS) attack.


5) 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.


6) Input validation error (CVE-ID: CVE-2021-30641)

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

The vulnerability exists due to incorrect parsing of Apache configuration files. An unexpected section could be matched with 'MergeSlashes OFF' option, leading to a potential security issue.


7) NULL pointer dereference (CVE-ID: CVE-2021-31618)

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_http2 in Apache HTTP server. A remote attacker can send specially crafted request to the server and perform a denial of service (DoS) attack.


Remediation

Install update from vendor's website.