CVE-2016-10003

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 4.8% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2017-01-27 · updated 2026-06-17
Weakness: CWE-697

Description

Incorrect HTTP Request header comparison in Squid HTTP Proxy 3.5.0.1 through 3.5.22, and 4.0.1 through 4.0.16 results in Collapsed Forwarding feature mistakenly identifying some private responses as being suitable for delivery to multiple clients.

Affected products

Squid: from 3.5.0.1 before 3.5.23; from 4.0.1 before 4.0.17 — fixed in 3.5.23, 4.0.17

How to fix

Upgrade to a fixed version: Squid 3.5.23, 4.0.17. Check the vendor advisory for mitigations.

References

http://www.openwall.com/lists/oss-security/2016/12/18/1
http://www.securityfocus.com/bid/94953
http://www.securitytracker.com/id/1037512
http://www.squid-cache.org/Advisories/SQUID-2016_10.txt
http://www.openwall.com/lists/oss-security/2016/12/18/1
http://www.securityfocus.com/bid/94953
http://www.securitytracker.com/id/1037512
http://www.squid-cache.org/Advisories/SQUID-2016_10.txt

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