Rapid7

vulnerability

Red Hat: CVE-2019-20637: CVE-2019-20637 varnish: not clearing pointer between two client requests leads to information disclosure (Multiple Advisories)

Severity
5
CVSS
(AV:N/AC:L/Au:N/C:P/I:N/A:N)
Published
Apr 8, 2020
Added
Nov 5, 2020
Modified
Mar 27, 2026

Description

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.

Solutions

redhat-upgrade-varnishredhat-upgrade-varnish-develredhat-upgrade-varnish-docsredhat-upgrade-varnish-modulesredhat-upgrade-varnish-modules-debuginforedhat-upgrade-varnish-modules-debugsource
Title
Rapid7 Labs

2026 Global Threat Landscape Report

The predictive window has collapsed. Exploitation follows disclosure in days. See how attackers are accelerating and how to stay ahead.