CVE-2015-4171

Severity: low (CVSS 2.6 v2.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 2.0% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2015-06-10 · updated 2026-06-17
Weakness: CWE-200

Description

strongSwan 4.3.0 through 5.x before 5.3.2 and strongSwan VPN Client before 1.4.6, when using EAP or pre-shared keys for authenticating an IKEv2 connection, does not enforce server authentication restrictions until the entire authentication process is complete, which allows remote servers to obtain credentials by using a valid certificate and then reading the responses.

Affected products

Canonical Ubuntu Linux: 14.04, 14.10, 15.04
Debian Linux: 8.0
strongSwan: 4.3.0, 4.3.1, 4.3.2, 4.3.3, 4.3.4, 4.3.5 (+28)
Strongswan Vpn Client: through 1.4.5

References

http://lists.opensuse.org/opensuse-updates/2015-06/msg00040.html
http://www.debian.org/security/2015/dsa-3282
http://www.openwall.com/lists/oss-security/2015/05/29/6
http://www.openwall.com/lists/oss-security/2015/05/29/7
http://www.openwall.com/lists/oss-security/2015/06/08/4
http://www.securityfocus.com/bid/74933
http://www.securitytracker.com/id/1032514
http://www.ubuntu.com/usn/USN-2628-1
https://bugzilla.suse.com/show_bug.cgi?id=933591
https://play.google.com/store/apps/details?id=org.strongswan.android
https://www.strongswan.org/blog/2015/06/08/strongswan-vulnerability-%2528cve-2015-4171%2529.html
https://www.suse.com/security/cve/CVE-2015-4171.html

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