The process_as_req function in the Key Distribution Center (KDC) in MIT Kerberos 5 (aka krb5) 1.10.x before 1.10.3 does not initialize a certain structure member, which allows remote attackers to cause a denial of service (uninitialized pointer dereference and daemon crash) or possibly execute arbitrary code via a malformed AS-REQ request.

Several potential codeexecution flaws were fixed in krb5.

The remote host is affected by the vulnerability described in GLSA-201312-12 (MIT Kerberos 5: Multiple vulnerabilities)

    Multiple vulnerabilities have been discovered in the Key Distribution       Center in MIT Kerberos 5. Please review the CVE identifiers referenced       below for details.
  Impact :

    A remote attacker could send a specially crafted request, possibly       resulting in execution of arbitrary code with the privileges of the       process or a Denial of Service condition. Additionally, a remote attacker       could impersonate a kadmind server and send a specially crafted packet to       the password change port, which can result in a ping-pong condition and a       Denial of Service condition.
  Workaround :

    There is no known workaround at this time.

This update incorporates the upstream fixes for CVE-2012-1014 and CVE-2012-1015, in which the KDC could be made to attempt to dereference or free an uninitialized pointer.

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.

Emmanuel Bouillon discovered that the MIT krb5 Key Distribution Center (KDC) daemon could free an uninitialized pointer when handling a malformed AS-REQ message. A remote unauthenticated attacker could use this to cause a denial of service or possibly execute arbitrary code.
(CVE-2012-1015)

Emmanuel Bouillon discovered that the MIT krb5 Key Distribution Center (KDC) daemon could dereference an uninitialized pointer while handling a malformed AS-REQ message. A remote unauthenticated attacker could use this to cause a denial of service or possibly execute arbitrary code. This issue only affected Ubuntu 12.04 LTS. (CVE-2012-1014)

Simo Sorce discovered that the MIT krb5 Key Distribution Center (KDC) daemon could dereference a NULL pointer when handling a malformed TGS-REQ message. A remote authenticated attacker could use this to cause a denial of service. (CVE-2012-1013)

It was discovered that the kadmin protocol implementation in MIT krb5 did not properly restrict access to the SET_STRING and GET_STRINGS operations. A remote authenticated attacker could use this to expose or modify sensitive information. This issue only affected Ubuntu 12.04 LTS. (CVE-2012-1012).

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

Emmanuel Bouillon from NCI Agency discovered multiple vulnerabilities in MIT Kerberos, a daemon implementing the network authentication protocol.

  - CVE-2012-1014     By sending specially crafted AS-REQ (Authentication     Service Request) to a KDC (Key Distribution Center), an     attacker could make it free an uninitialized pointer,     corrupting the heap. This can lead to process crash or     even arbitrary code execution.

  This CVE only affects testing (wheezy) and unstable (sid)   distributions.

  - CVE-2012-1015     By sending specially crafted AS-REQ to a KDC, an     attacker could make it dereference an uninitialized     pointer, leading to process crash or even arbitrary code     execution

In both cases, arbitrary code execution is believed to be difficult to achieve, but might not be impossible.

ID	Name	Product	Family	Severity
74706	openSUSE Security Update : krb5 (openSUSE-SU-2012:0967-1)	Nessus	SuSE Local Security Checks	high
71487	GLSA-201312-12 : MIT Kerberos 5: Multiple vulnerabilities	Nessus	Gentoo Local Security Checks	high
61425	Fedora 17 : krb5-1.10.2-6.fc17 (2012-11388)	Nessus	Fedora Local Security Checks	high
61379	Ubuntu 10.04 LTS / 11.04 / 11.10 / 12.04 LTS : krb5 vulnerabilities (USN-1520-1)	Nessus	Ubuntu Local Security Checks	high
61374	Debian DSA-2518-1 : krb5 - denial of service and remote code execution	Nessus	Debian Local Security Checks	high

Detections

Analytics

CVE-2012-1014

critical

Tenable Plugins

high

high

high

high

high