strongSwan 4.3.5 through 5.0.3, when using the OpenSSL plugin for ECDSA signature verification, allows remote attackers to authenticate as other users via an invalid signature.

- Applied upstream patch for security vulnerability     discovered by Kevin Wojtysiak in ECDSA signature     verification of the strongswan openssl plugin     (bnc#815236, CVE-2013-2944)     [0003-Check-return-value-of-ECDSA_Verify-correctly.patch     ]

The remote host is affected by the vulnerability described in GLSA-201309-02 (strongSwan: Multiple vulnerabilities)

    Multiple vulnerabilities have been discovered in strongSwan. Please       review the CVE identifiers referenced below for details.
  Impact :

    A remote attacker could use ECDSA to authenticate as another user with       an invalid signature. Additionally, a remote attacker could send a       specially crafted request, possibly resulting in a Denial of Service.
  Workaround :

    There is no known workaround at this time.

This update fixes the ECDSA signature vulnerability in strongswan.
CVE-2013-2944 was assigned to this issue.

This update fixes the ECDSA signature vulnerability in strongswan.
CVE-2013-2944 has been assigned to this issue.

strongSwan security team reports :

If the openssl plugin is used for ECDSA signature verification an empty, zeroed or otherwise invalid signature is handled as a legitimate one. Both IKEv1 and IKEv2 are affected.

Affected are only installations that have enabled and loaded the OpenSSL crypto backend (--enable-openssl). Builds using the default crypto backends are not affected.

Kevin Wojtysiak discovered a vulnerability in strongSwan, an IPsec based VPN solution.

When using the OpenSSL plugin for ECDSA based authentication, an empty, zeroed or otherwise invalid signature is handled as a legitimate one. An attacker could use a forged signature to authenticate like a legitimate user and gain access to the VPN (and everything protected by this).

While the issue looks like CVE-2012-2388 (RSA signature based authentication bypass), it is unrelated.

ID	Name	Product	Family	Severity
74995	openSUSE Security Update : strongswan (openSUSE-SU-2013:0774-1)	Nessus	SuSE Local Security Checks	medium
74994	openSUSE Security Update : strongswan (openSUSE-SU-2013:0775-1)	Nessus	SuSE Local Security Checks	medium
74993	openSUSE Security Update : strongswan (openSUSE-SU-2013:0873-1)	Nessus	SuSE Local Security Checks	medium
69539	GLSA-201309-02 : strongSwan: Multiple vulnerabilities	Nessus	Gentoo Local Security Checks	medium
69192	SuSE 11.3 Security Update : strongswan (SAT Patch Number 8021)	Nessus	SuSE Local Security Checks	medium
69191	SuSE 11.3 Security Update : strongswan (SAT Patch Number 8021)	Nessus	SuSE Local Security Checks	medium
69055	SuSE 10 Security Update : strongswan (ZYPP Patch Number 8546)	Nessus	SuSE Local Security Checks	medium
69030	SuSE 11.2 Security Update : strongswan (SAT Patch Number 7638)	Nessus	SuSE Local Security Checks	medium
66312	FreeBSD : strongSwan -- ECDSA signature verification issue (6ff570cb-b418-11e2-b279-20cf30e32f6d)	Nessus	FreeBSD Local Security Checks	medium
66281	Debian DSA-2665-1 : strongswan - authentication bypass	Nessus	Debian Local Security Checks	medium

Detections

Analytics

CVE-2013-2944

high

Tenable Plugins

medium

medium

medium

medium

medium

medium

medium

medium

medium

medium