The check_1_6_dummy function in lib/kadm5/srv/svr_principal.c in kadmind in MIT Kerberos 5 (aka krb5) 1.8.x, 1.9.x, and 1.10.x before 1.10.2 allows remote authenticated administrators to cause a denial of service (NULL pointer dereference and daemon crash) via a KRB5_KDB_DISALLOW_ALL_TIX create request that lacks a password.

Fixing CVE-2012-1013 (krb5 kadmind denial of service via NULL pointer dereference)

An uninitialized pointer use flaw was found in the way the MIT Kerberos KDC handled initial authentication requests (AS-REQ). A remote, unauthenticated attacker could use this flaw to crash the KDC via a specially crafted AS-REQ request. (CVE-2012-1015)

A NULL pointer dereference flaw was found in the MIT Kerberos administration daemon, kadmind. A Kerberos administrator who has the 'create' privilege could use this flaw to crash kadmind.
(CVE-2012-1013)

From Red Hat Security Advisory 2012:1131 :

Updated krb5 packages that fix two security issues are now available for Red Hat Enterprise Linux 6.

The Red Hat Security Response Team has rated this update as having important security impact. Common Vulnerability Scoring System (CVSS) base scores, which give detailed severity ratings, are available for each vulnerability from the CVE links in the References section.

Kerberos is a network authentication system which allows clients and servers to authenticate to each other using symmetric encryption and a trusted third-party, the Key Distribution Center (KDC).

An uninitialized pointer use flaw was found in the way the MIT Kerberos KDC handled initial authentication requests (AS-REQ). A remote, unauthenticated attacker could use this flaw to crash the KDC via a specially crafted AS-REQ request. (CVE-2012-1015)

A NULL pointer dereference flaw was found in the MIT Kerberos administration daemon, kadmind. A Kerberos administrator who has the 'create' privilege could use this flaw to crash kadmind.
(CVE-2012-1013)

Red Hat would like to thank the MIT Kerberos project for reporting CVE-2012-1015. Upstream acknowledges Emmanuel Bouillon (NCI Agency) as the original reporter of CVE-2012-1015.

All krb5 users should upgrade to these updated packages, which contain backported patches to correct these issues. After installing the updated packages, the krb5kdc and kadmind daemons will be restarted automatically.

Updated krb5 packages that fix two security issues are now available for Red Hat Enterprise Linux 6.

The Red Hat Security Response Team has rated this update as having important security impact. Common Vulnerability Scoring System (CVSS) base scores, which give detailed severity ratings, are available for each vulnerability from the CVE links in the References section.

Kerberos is a network authentication system which allows clients and servers to authenticate to each other using symmetric encryption and a trusted third-party, the Key Distribution Center (KDC).

An uninitialized pointer use flaw was found in the way the MIT Kerberos KDC handled initial authentication requests (AS-REQ). A remote, unauthenticated attacker could use this flaw to crash the KDC via a specially crafted AS-REQ request. (CVE-2012-1015)

A NULL pointer dereference flaw was found in the MIT Kerberos administration daemon, kadmind. A Kerberos administrator who has the 'create' privilege could use this flaw to crash kadmind.
(CVE-2012-1013)

Red Hat would like to thank the MIT Kerberos project for reporting CVE-2012-1015. Upstream acknowledges Emmanuel Bouillon (NCI Agency) as the original reporter of CVE-2012-1015.

All krb5 users should upgrade to these updated packages, which contain backported patches to correct these issues. After installing the updated packages, the krb5kdc and kadmind daemons will be restarted automatically.

Multiple vulnerabilities has been discovered and corrected in krb5 :

Fix a kadmind denial of service issue (NULL pointer dereference), which could only be triggered by an administrator with the create privilege (CVE-2012-1013).

The MIT krb5 KDC (Key Distribution Center) daemon can free an uninitialized pointer while processing an unusual AS-REQ, corrupting the process heap and possibly causing the daemon to abnormally terminate. An attacker could use this vulnerability to execute malicious code, but exploiting frees of uninitialized pointers to execute code is believed to be difficult. It is possible that a legitimate client that is misconfigured in an unusual way could trigger this vulnerability (CVE-2012-1015).

It was reported that the KDC plugin for PKINIT could dereference a NULL pointer when a malformed packet caused processing to terminate early, which led to a crash of the KDC process. An attacker would require a valid PKINIT certificate or have observed a successful PKINIT authentication to execute a successful attack. In addition, an unauthenticated attacker could execute the attack of anonymouse PKINIT was enabled (CVE-2013-1415).

The updated packages have been patched to correct these issues.

Kerberos is a network authentication system which allows clients and servers to authenticate to each other using symmetric encryption and a trusted third party, the Key Distribution Center (KDC).

An uninitialized pointer use flaw was found in the way the MIT Kerberos KDC handled initial authentication requests (AS-REQ). A remote, unauthenticated attacker could use this flaw to crash the KDC via a specially crafted AS-REQ request. (CVE-2012-1015)

A NULL pointer dereference flaw was found in the MIT Kerberos administration daemon, kadmind. A Kerberos administrator who has the 'create' privilege could use this flaw to crash kadmind.
(CVE-2012-1013)

All krb5 users should upgrade to these updated packages, which contain backported patches to correct these issues. After installing the updated packages, the krb5kdc and kadmind daemons will be restarted automatically.

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.

A vulnerability has been discovered and corrected in krb5 :

Fix a kadmind denial of service issue (NULL pointer dereference), which could only be triggered by an administrator with the create privilege (CVE-2012-1013).

The updated packages have been patched to correct this issue.

This update incorporates the upstream fix to correct a possible NULL pointer dereference in kadmind (CVE-2012-1013).

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.

ID	Name	Product	Family	Severity
74662	openSUSE Security Update : krb5 (openSUSE-SU-2012:0834-1)	Nessus	SuSE Local Security Checks	medium
69604	Amazon Linux AMI : krb5 (ALAS-2012-114)	Nessus	Amazon Linux Local Security Checks	high
68589	Oracle Linux 6 : krb5 (ELSA-2012-1131)	Nessus	Oracle Linux Local Security Checks	high
67093	CentOS 6 : krb5 (CESA-2012:1131)	Nessus	CentOS Local Security Checks	high
66056	Mandriva Linux Security Advisory : krb5 (MDVSA-2013:042)	Nessus	Mandriva Local Security Checks	high
61407	Scientific Linux Security Update : krb5 on SL6.x i386/x86_64 (20120731)	Nessus	Scientific Linux 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
61377	RHEL 6 : krb5 (RHSA-2012:1131)	Nessus	Red Hat Local Security Checks	high
59860	Mandriva Linux Security Advisory : krb5 (MDVSA-2012:102)	Nessus	Mandriva Local Security Checks	medium
59486	Fedora 15 : krb5-1.9.3-2.fc15 (2012-8805)	Nessus	Fedora Local Security Checks	medium
59485	Fedora 16 : krb5-1.9.3-2.fc16 (2012-8803)	Nessus	Fedora Local Security Checks	medium
59484	Fedora 17 : krb5-1.10-7.fc17 (2012-8784)	Nessus	Fedora Local Security Checks	medium

Detections

Analytics

CVE-2012-1013

high

Tenable Plugins

medium

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high

medium

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medium