SB2016122402 - Slackware Linux update for httpd
Published: December 24, 2016
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 5 secuirty vulnerabilities.
1) Memory leak (CVE-ID: CVE-2016-8740)
The vulnerability allows a remote attacker to cause denial of service.
The vulnerability exists due to improper handling of HTTP/2 headers, when the Protocols configuration includes h2 or h2c. A remote attacker can send a specially crafted HTTP/2 request, containign CONTINUATION frames to vulnerable instance and consume all available memory resources.
Successful exploitation of the vulnerability will result in denial of service (DoS) of affected web server.
2) Httpoxy issue (CVE-ID: CVE-2016-5387)
The vulnerability allows a remote attacker to obtain potentially sensitive information and compromise vulnerable server.
The vulnerability exists due to a design error in multiple implementations of web servers. A remote unauthenticated attacker can use a specially crafted Proxy header in HTTP request to influence HTTP_PROXY environment variable and redirect application’s HTTP traffic to arbitrary proxy server.
Successful exploitation of this vulnerability may allow an attacker to gain unauthorized access to sensitive information and compromise vulnerable server.
This vulnerability is known as httppoxy.
3) Improper input validation (CVE-ID: CVE-2016-2161)
The vulnerability allows a remote attacker to cause denial of service attack.The vulnerability exists due to input validation error in mod_auth_digest module when parsing malicious HTTP requests. A remote attacker can send a specially crafted HTTP request to affected server and cause server crash.
Successful exploitation of the vulnerability will result in crash of each server instance.
4) Padding oracle attack (CVE-ID: CVE-2016-0736)
The vulnerability allows a remote attacker to obtain potentially sensitive information.The vulnerability exists due to an error in Apache mod_session_crypto implementation. A remote attacker with ability to intercept traffic can decipher potentially sensitive information or tamper with data.
Successful exploitation may allow an attacker to perform padding oracle attack against vulnerable web server and obtain potentially sensitive information.
5) Spoofing attack (CVE-ID: CVE-2016-8743)
The vulnerability allows a remote attacker to perform spoofing attack.
The vulnerability exists due to insufficient sanitization of HTTP request, which contain whitespace characters. A remote attacker can send a specially crafted HTTP request, containing CR, FF, VTAB characters followed by CRLF sequence and inject arbitrary data in server response.
Successful exploitation of this vulnerability may result in content spoofing, web cache poisoning and XSS attacks.
Remediation
Install update from vendor's website.