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Vulnerability record · CVE-2016-2390 · published 19 April 2016

CVE-2016-2390: Squid-cache squid improper input validation vulnerability

Squid Cache · Squid

The FwdState::connectedToPeer method in FwdState.cc in Squid before 3.5.14 and 4.0.x before 4.0.6 does not properly handle SSL handshake errors when built with the --with-openssl option, which allows remote attackers to cause a denial of service (application crash) via a plaintext HTTP message.

5.9 CVSS 3.0 Medium EPSS 26% · top 2.1% CWE-20 · Improper input validation
5.9CVSS 3.0 base score, v2 4.3
26%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
14References
17 Jun 2026Last modified by NVD

Description

The FwdState::connectedToPeer method in FwdState.cc in Squid before 3.5.14 and 4.0.x before 4.0.6 does not properly handle SSL handshake errors when built with the --with-openssl option, which allows remote attackers to cause a denial of service (application crash) via a plaintext HTTP message.

CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
http://bugs.squid-cache.org/show_bug.cgi?id=4437
http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00010.html
http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00040.html
http://lists.squid-cache.org/pipermail/squid-announce/2016-February/000037.html Vendor Advisory
http://lists.squid-cache.org/pipermail/squid-announce/2016-February/000038.html Vendor Advisory
http://www.securitytracker.com/id/1035045
http://www.squid-cache.org/Advisories/SQUID-2016_1.txt Vendor Advisory
http://bugs.squid-cache.org/show_bug.cgi?id=4437
http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00010.html
http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00040.html
http://lists.squid-cache.org/pipermail/squid-announce/2016-February/000037.html Vendor Advisory
http://lists.squid-cache.org/pipermail/squid-announce/2016-February/000038.html Vendor Advisory
http://www.securitytracker.com/id/1035045
http://www.squid-cache.org/Advisories/SQUID-2016_1.txt Vendor Advisory

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Source: NIST National Vulnerability Database (record CVE-2016-2390), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.