Vulnerability identifier: #VU42408

Vulnerability risk: Medium

CVSSv3.1: 4.6 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L/E:U/RL:O/RC:C]

CVE-ID: CVE-2013-6075

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
strongSwan
Server applications / Encryption software

Vendor: strongswan.org

Description

The vulnerability allows (1) remote attackers to cause a denial of service (out-of-bounds read, NULL pointer dereference, and daemon crash) or (2) remote authenticated users to perform a denial of service (DoS) attack.

The vulnerability exists due to insufficient validation of user-supplied input. A remote attacker can impersonate arbitrary users and bypass access restrictions via a crafted ID_DER_ASN1_DN ID, related to an "insufficient length check" during identity comparison.

Mitigation
Install update from vendor's website.

Vulnerable software versions

strongSwan: 4.3.3 - 5.1.0

---

External links
http://download.strongswan.org/security/CVE-2013-6075/strongswan-4.3.3-5.1.0_id_dn_match.patch
http://www.debian.org/security/2012/dsa-2789
http://www.strongswan.org/blog/2013/11/01/strongswan-denial-of-service-vulnerability-%28cve-2013-6075%29.html

---

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.