CVE-2022-23959

2022-01-2713:58:04

redhat.com

access.redhat.com

varnish

request smuggling

http/1

vcl processing

mitigation

CVSS2

6.4

Attack Vector

NETWORK

Attack Complexity

LOW

Authentication

NONE

Confidentiality Impact

PARTIAL

Integrity Impact

PARTIAL

Availability Impact

NONE

AV:N/AC:L/Au:N/C:P/I:P/A:N

CVSS3

9.1

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

NONE

User Interaction

NONE

Scope

UNCHANGED

Confidentiality Impact

HIGH

Integrity Impact

HIGH

Availability Impact

NONE

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

EPSS

0.005

Percentile

77.6%

JSON

A flaw was found in Varnish. This flaw allows an attacker to carry out a request smuggling attack on HTTP/1 connections on Varnish cache servers. This smuggled request goes through the usual Varnish Configuration Language (VCL) processing since the Varnish server treats it as an additional request.

Mitigation

This issue can be mitigated by ensuring that the Varnish server does not allow connection reuse on HTTP/1 client connections once a request body has been seen on the connection. This requires changes in the VCL configuration.