IKEv2 in strongSwan 4.0.7 before 5.1.3 allows remote attackers to bypass authentication by rekeying an IKE_SA during (1) initiation or (2) re-authentication, which triggers the IKE_SA state to be set to established.

The remote host is affected by the vulnerability described in GLSA-201412-26 (strongSwan: Multiple Vulnerabilities)

    A NULL pointer dereference and an error in the IKEv2 implementation have       been found in strongSwan.
  Impact :

    A remote attacker could create a Denial of Service condition or bypass       security restrictions.
  Workaround :

    There is no known workaround at this time.

strongswan was fixed to correct two issues :

  - Fix for DoS vulnerability by a NULL pointer dereference     (CVE-2014-2891).

  - Fix for a authentication bypass vulnerability in the     IKEv2 code (CVE-2014-2338).

strongSwan developers report :

Remote attackers are able to bypass authentication by rekeying an IKE_SA during (1) initiation or (2) re-authentication, which triggers the IKE_SA state to be set to established.

Only installations that actively initiate or re-authenticate IKEv2 IKE_SAs are affected.

This update fixes :

  - Bug #1081760 - CVE-2014-2338 strongswan: authentication     bypass flaw in IKEv2

Note that Tenable Network Security has extracted the preceding description block directly from the Fedora security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

The following security issue is fixed by this update :

  - strongswan has been updated to fix an authentication     problem where attackers could have bypassed the IKEv2     authentication. (CVE-2014-2338). (bnc#870572)

An authentication bypass vulnerability was found in charon, the daemon handling IKEv2 in strongSwan, an IKE/IPsec suite. The state machine handling the security association (IKE_SA) handled some state transitions incorrectly.

An attacker can trigger the vulnerability by rekeying an unestablished IKE_SA during the initiation itself. This will trick the IKE_SA state to'established' without the need to provide any valid credential.

Vulnerable setups include those actively initiating IKEv2 IKE_SA (like 'clients' or 'roadwarriors') but also during re-authentication (which can be initiated by the responder). Installations using IKEv1 (pluto daemon in strongSwan 4 and earlier, and IKEv1 code in charon 5.x) is not affected.

ID	Name	Product	Family	Severity
79979	GLSA-201412-26 : strongSwan: Multiple Vulnerabilities	Nessus	Gentoo Local Security Checks	medium
75367	openSUSE Security Update : strongswan (openSUSE-SU-2014:0697-1)	Nessus	SuSE Local Security Checks	medium
73857	FreeBSD : strongswan -- Remote Authentication Bypass (6fb521b0-d388-11e3-a790-000c2980a9f3)	Nessus	FreeBSD Local Security Checks	medium
73699	Fedora 20 : strongswan-5.1.3-1.fc20 (2014-5231)	Nessus	Fedora Local Security Checks	medium
73555	SuSE 11.3 Security Update : strongswan (SAT Patch Number 9089)	Nessus	SuSE Local Security Checks	medium
73501	Debian DSA-2903-1 : strongswan - security update	Nessus	Debian Local Security Checks	medium

Detections

Analytics

CVE-2014-2338

critical

Tenable Plugins

medium

medium

medium

medium

medium

medium