Information disclosure in Varnish Cache - CVE-2019-20637
Published: April 9, 2020 / Updated: July 17, 2020
Vulnerability identifier: #VU30309
CSH Severity: Medium
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2019-20637
CWE-ID: CWE-200
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: Varnish Software
Affected software:
Varnish Cache
Varnish Cache
Detailed vulnerability description
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.
How to mitigate CVE-2019-20637
Install update from vendor's website.