CVE-2015-4171

low
Published 2015-06-10 · Modified 2026-05-06
CVSS v3
CVSS v2
2.6
VIR risk
2.6

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.

Predictions

Exploit likelihood
20%
Patch ETA

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

vendor Authored 2026-05-27

Vendor advisory: debian — https://security-tracker.debian.org/tracker/CVE-2015-4171

vendor Authored 2026-05-27

Vendor advisory: cve@mitre.org — https://www.strongswan.org/blog/2015/06/08/strongswan-vulnerability-%2528cve-2015-4171%2529.html

vendor Authored 2026-05-27

Vendor advisory: cve@mitre.org — https://play.google.com/store/apps/details?id=org.strongswan.android

vendor Authored 2026-05-27

Vendor advisory: cve@mitre.org — http://www.ubuntu.com/usn/USN-2628-1

vendor Authored 2026-05-27

Vendor advisory: cve@mitre.org — http://www.debian.org/security/2015/dsa-3282

OS impact

OSVersionStatusFixed in
debian debian8.0affected
ubuntu ubuntu14.04affected
ubuntu ubuntu14.10affected
ubuntu ubuntu15.04affected
debian debianbookwormfixed5.3.1-1
debian debianbullseyefixed5.3.1-1
debian debianforkyfixed5.3.1-1
debian debiansidfixed5.3.1-1
debian debiantrixiefixed5.3.1-1

Application impact

VendorProductVersionsFixed
strongswanstrongswan_vpn_client{"endIncluding":"1.4.5"}
strongswanstrongswan4.3.0
strongswanstrongswan4.3.1
strongswanstrongswan4.3.2
strongswanstrongswan4.3.3
strongswanstrongswan4.3.4
strongswanstrongswan4.3.5
strongswanstrongswan4.3.6
strongswanstrongswan4.3.7
strongswanstrongswan4.4.0
strongswanstrongswan4.4.1
strongswanstrongswan4.5.0
strongswanstrongswan4.5.1
strongswanstrongswan4.5.2
strongswanstrongswan4.5.3
strongswanstrongswan4.6.0
strongswanstrongswan4.6.1
strongswanstrongswan4.6.2
strongswanstrongswan4.6.3
strongswanstrongswan4.6.4
strongswanstrongswan5.0.0
strongswanstrongswan5.0.1
strongswanstrongswan5.0.2
strongswanstrongswan5.0.3
strongswanstrongswan5.0.4
strongswanstrongswan5.1.0
strongswanstrongswan5.1.1
strongswanstrongswan5.1.2
strongswanstrongswan5.1.3
strongswanstrongswan5.2.0
strongswanstrongswan5.2.1
strongswanstrongswan5.2.2
strongswanstrongswan5.2.3
strongswanstrongswan5.3.0
strongswanstrongswan5.3.1

References

CWEs

CWE-200

Verify integrity in audit chain (admin only). AS-IS.