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Bug 490634 (CVE-2009-0845)

Summary: CVE-2009-0845 krb5: NULL pointer dereference in GSSAPI SPNEGO (MITKRB5-SA-2009-001)
Product: [Other] Security Response Reporter: Jan Lieskovsky <jlieskov>
Component: vulnerabilityAssignee: Red Hat Product Security <security-response-team>
Status: CLOSED ERRATA QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: unspecifiedCC: kreilly, mjc, nalin, security-response-team, vdanen
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
URL: http://krbdev.mit.edu/rt/Ticket/Display.html?user=guest&pass=guest&id=6402
Whiteboard: source=vendorsec,impact=important,reported=20090313,public=20090313,cvss2=4.3/AV:N/AC:M/Au:N/C:N/I:N/A:P,cwe=CWE-476[auto]
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2009-04-09 05:35:20 EDT Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: ---
Bug Depends On: 490635, 490636    
Bug Blocks:    

Description Jan Lieskovsky 2009-03-17 08:46:15 EDT
A null pointer dereference flaw was found in Kerberos's GSS-API spnego
security mechanism implemenation. A local user could use this flaw
to cause a denial of service (krb5 daemon crash) via invalid ContextFlags for
the reqFlags field in the NegTokenInit (RFC 4178).

References:
http://krbdev.mit.edu/rt/Ticket/Display.html?user=guest&pass=guest&id=6402

Upstream patch:
http://src.mit.edu/fisheye/changelog/krb5/?cs=22099
Comment 2 Fedora Update System 2009-03-17 19:00:49 EDT
krb5-1.6.3-17.fc10 has been submitted as an update for Fedora 10.
http://admin.fedoraproject.org/updates/krb5-1.6.3-17.fc10
Comment 3 Fedora Update System 2009-03-17 19:01:09 EDT
krb5-1.6.3-15.fc9 has been submitted as an update for Fedora 9.
http://admin.fedoraproject.org/updates/krb5-1.6.3-15.fc9
Comment 4 Tomas Hoger 2009-03-18 04:20:18 EDT
This issue did not affect the versions of krb5 as shipped with Red Hat Enterprise Linux 2.1, 3, and 4.
Comment 5 Mark J. Cox 2009-03-18 05:07:35 EDT
Upstream commit:
http://anonsvn.mit.edu/cgi-bin/viewcvs.cgi?rev=22084&view=rev
Comment 9 Vincent Danen 2009-03-27 14:42:31 EDT
Common Vulnerabilities and Exposures assigned an identifier CVE-2009-0845 to
the following vulnerability:

Name: CVE-2009-0845
URL: http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2009-0845
Assigned: 20090306
Reference: CONFIRM: http://krbdev.mit.edu/rt/Ticket/Display.html?user=guest&pass=guest&id=6402
Reference: CONFIRM: http://src.mit.edu/fisheye/browse/krb5/trunk/src/lib/gssapi/spnego/spnego_mech.c?r1=21875&r2=22084
Reference: CONFIRM: http://src.mit.edu/fisheye/changelog/krb5/?cs=22084
Reference: BID:34257
Reference: URL: http://www.securityfocus.com/bid/34257
Reference: SECUNIA:34347
Reference: URL: http://secunia.com/advisories/34347
Reference: VUPEN:ADV-2009-0847
Reference: URL: http://www.vupen.com/english/advisories/2009/0847 The spnego_gss_accept_sec_context function in
lib/gssapi/spnego/spnego_mech.c in MIT Kerberos 5 (aka krb5) 1.6.3,
when SPNEGO is used, allows remote attackers to cause a denial of
service (NULL pointer dereference and application crash) via invalid
ContextFlags data in the reqFlags field in a negTokenInit token.
Comment 10 Tomas Hoger 2009-04-07 14:20:56 EDT
Covered now in upstream security advisory:
  http://web.mit.edu/kerberos/advisories/MITKRB5-SA-2009-001.txt

Final upstream patch differs from the previous one:
  https://bugzilla.redhat.com/show_bug.cgi?id=491033#c7
Comment 11 errata-xmlrpc 2009-04-07 14:47:45 EDT
This issue has been addressed in following products:

  Red Hat Enterprise Linux 5

Via RHSA-2009:0408 https://rhn.redhat.com/errata/RHSA-2009-0408.html
Comment 12 Fedora Update System 2009-04-07 19:23:02 EDT
krb5-1.6.3-16.fc9 has been pushed to the Fedora 9 stable repository.  If problems still persist, please make note of it in this bug report.
Comment 13 Fedora Update System 2009-04-07 19:23:22 EDT
krb5-1.6.3-18.fc10 has been pushed to the Fedora 10 stable repository.  If problems still persist, please make note of it in this bug report.