SB2022060903 - Ubuntu update for varnish
Published: June 9, 2022
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 4 secuirty vulnerabilities.
1) Information disclosure (CVE-ID: CVE-2019-20637)
The vulnerability allows a remote non-authenticated attacker to gain access to sensitive information.
An issue was discovered in Varnish Cache before 6.0.5 LTS, 6.1.x and 6.2.x before 6.2.2, and 6.3.x before 6.3.1. It does not clear a pointer between the handling of one client request and the next request within the same connection. This sometimes causes information to be disclosed from the connection workspace, such as data structures associated with previous requests within this connection or VCL-related temporary headers.
2) Input validation error (CVE-ID: CVE-2020-11653)
The vulnerability allows a remote non-authenticated attacker to perform a denial of service (DoS) attack.
An issue was discovered in Varnish Cache before 6.0.6 LTS, 6.1.x and 6.2.x before 6.2.3, and 6.3.x before 6.3.2. It occurs when communication with a TLS termination proxy uses PROXY version 2. There can be an assertion failure and daemon restart, which causes a performance loss.
3) Inconsistent interpretation of HTTP requests (CVE-ID: CVE-2021-36740)
The vulnerability allows a remote attacker to preform HTTP request smuggling attacks.
The vulnerability exists due to improper validation of HTTP/2 requests. A remote attacker can send a specially crafted HTTP/2 POST request with a large Content-Length header to the server and smuggle arbitrary HTTP headers.
Successful exploitation of vulnerability may allow an attacker to poison HTTP cache or bypass VCL authorization.
4) Inconsistent interpretation of HTTP requests (CVE-ID: CVE-2022-23959)
The vulnerability allows a remote attacker to preform HTTP request smuggling attacks.
The vulnerability exists due to improper validation of HTTP/1 requests. A remote attacker can send a specially crafted HTTP/1 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.
Remediation
Install update from vendor's website.