Access Restriction Bypass Affecting squid package, versions <4.1-1


Severity

Recommended
0.0
medium
0
10

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Threat Intelligence

EPSS
3.09% (86th percentile)

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  • Snyk IDSNYK-ECHOLATEST-SQUID-18291652
  • published24 Jul 2026
  • disclosed4 Mar 2009

Introduced: 4 Mar 2009

CVE-2009-0801  (opens in a new tab)
CWE-264  (opens in a new tab)

How to fix?

Upgrade Echo:latest squid to version 4.1-1 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream squid package and not the squid package as distributed by Echo. See How to fix? for Echo:latest relevant fixed versions and status.

Squid, when transparent interception mode is enabled, uses the HTTP Host header to determine the remote endpoint, which allows remote attackers to bypass access controls for Flash, Java, Silverlight, and probably other technologies, and possibly communicate with restricted intranet sites, via a crafted web page that causes a client to send HTTP requests with a modified Host header.

CVSS Base Scores

version 3.1