CVE-2021-28543
Severity CVSS v4.0:
Pending analysis
Type:
CWE-476
NULL Pointer Dereference
Publication date:
16/03/2021
Last modified:
07/11/2023
Description
Varnish varnish-modules before 0.17.1 allows remote attackers to cause a denial of service (daemon restart) in some configurations. This does not affect organizations that only install the Varnish Cache product; however, it is common to install both Varnish Cache and varnish-modules. Specifically, an assertion failure or NULL pointer dereference can be triggered in Varnish Cache through the varnish-modules header.append() and header.copy() functions. For some Varnish Configuration Language (VCL) files, this gives remote clients an opportunity to cause a Varnish Cache restart. A restart reduces overall availability and performance due to an increased number of cache misses, and may cause higher load on backend servers.
Impact
Base Score 3.x
7.50
Severity 3.x
HIGH
Base Score 2.0
5.00
Severity 2.0
MEDIUM
Vulnerable products and versions
| CPE | From | Up to |
|---|---|---|
| cpe:2.3:a:varnish-cache:varnish-modules:*:*:*:*:*:*:*:* | 0.17.1 (excluding) | |
| cpe:2.3:a:varnish-cache:varnish-modules_klarlack:*:*:*:*:*:*:*:* | 0.17.1 (excluding) | |
| cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:* |
To consult the complete list of CPE names with products and versions, see this page



