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NULL Pointer Dereference The advisory has been revoked - it doesn't affect any version of package varnish-modules  (opens in a new tab)

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EPSS
0.2% (58th percentile)

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  • Snyk IDSNYK-DEBIAN11-VARNISHMODULES-1086517
  • published17 Mar 2021
  • disclosed16 Mar 2021
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Introduced: 16 Mar 2021

CVE-2021-28543  (opens in a new tab)
CWE-476  (opens in a new tab)

Amendment

The Debian security team deemed this advisory irrelevant for Debian:11.

NVD Description

Note: Versions mentioned in the description apply only to the upstream varnish-modules package and not the varnish-modules package as distributed by Debian.

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.