SB20200930100 - Red Hat Enterprise Linux 7 update for squid



SB20200930100 - Red Hat Enterprise Linux 7 update for squid

Published: September 30, 2020

Security Bulletin ID SB20200930100
Severity
High
Patch available
YES
Number of vulnerabilities 7
Exploitation vector Remote access
Highest impact Code execution

Breakdown by Severity

High 14% Medium 71% Low 14%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 7 secuirty vulnerabilities.


1) Out-of-bounds read (CVE-ID: CVE-2019-12528)

The vulnerability allows a remote attacker to gain access to potentially sensitive information.

The vulnerability exists due to a boundary condition when translating FTP server listing into HTTP responses. A remote attacker can trick the victim into vising a specially crafted FTP server, trigger out-of-bounds read and gain access to memory contents of the heap.


2) Input validation error (CVE-ID: CVE-2020-8449)

The vulnerability allows a remote attacker to gain access to sensitive information.

The vulnerability exists due to insufficient validation of user-supplied input when processing HTTP requests. A remote attacker can send a specially crafted HTTP request, bypass configured security filters and gain access to certain server resources.


3) Buffer overflow (CVE-ID: CVE-2020-8450)

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

The vulnerability exists due to a boundary error when processing HTTP requests, when Squid is acting as a reverse proxy. A remote attacker can send a specially crafted HTTP request to the affected proxy server, trigger memory corruption and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.


4) Inconsistent interpretation of HTTP requests (CVE-ID: CVE-2020-15049)

The vulnerability allows a remote attacker to perform cache poisoning attack.

The vulnerability exists in the way Squid processes client's requests. A remote client can send specially crafted data in the request to perform request smuggling and poison the HTTP cache contents with crafted HTTP(S) request messages.

Successful exploitation of the vulnerability requires an upstream server to participate in the smuggling and generate the poison response sequence.


5) Inconsistent interpretation of HTTP requests (CVE-ID: CVE-2020-15810)

The vulnerability allows a remote attacker to preform HTTP request smuggling attacks.

The vulnerability exists due to improper validation of HTTP requests. A remote authenticated attacker can send a specially crafted HTTP request to the server and smuggle arbitrary HTTP headers.

Successful exploitation of vulnerability may allow an attacker to poison HTTP cache and perform phishing attacks.


6) HTTP response splitting (CVE-ID: CVE-2020-15811)

The vulnerability allows a remote attacker to perform HTTP splitting attacks.

The vulnerability exists due to software does not corrector process CRLF character sequences. A remote authenticated attacker can send specially crafted request containing CRLF sequence and make the application to send a split HTTP response.

Successful exploitation of the vulnerability may allow an attacker perform cache poisoning attack.


7) Resource exhaustion (CVE-ID: CVE-2020-24606)

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

The vulnerability exists due to application does not properly EOF in peerDigestHandleReply() function in peer_digest.cc when processing Cache Digest response messages from a trusted peer. A remote attacker who controls a trusted peer can consume all available CPU cycles and perform a denial of service (DoS) attack.

This attack is limited to Squid using cache_peer with cache digests feature.


Remediation

Install update from vendor's website.