cbcvebase.
CVE-2021-28543
published 2021-03-16

CVE-2021-28543: 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…

PriorityP337high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EPSS
1.49%
71.3th percentile
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.

Affected

5 ranges
VendorProductVersion rangeFixed in
debianvarnish-modules
fedoraprojectfedora
msrccbl2_varnish-modules_on_cbl_mariner_2.0
varnish-cachevarnish-modules< 0.17.10.17.1
varnish-cachevarnish-modules_klarlack< 0.17.10.17.1

CVSS provenance

nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
nvdv2.05.0MEDIUMAV:N/AC:L/Au:N/C:N/I:N/A:P
vendor_debian4.0LOW
vendor_msrc4.0MEDIUM
vendor_redhat4.0MEDIUM
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