Secunia Security Advisory - Some vulnerabilities have been reported in Kerberos, which can be exploited by malicious users and malicious people to compromise a vulnerable system.
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TITLE:
Kerberos Multiple Vulnerabilities
SECUNIA ADVISORY ID:
SA26676
VERIFY ADVISORY:
http://secunia.com/advisories/26676/
CRITICAL:
Highly critical
IMPACT:
DoS, System access
WHERE:
>From remote
SOFTWARE:
Kerberos 5.x
http://secunia.com/product/556/
DESCRIPTION:
Some vulnerabilities have been reported in Kerberos, which can be
exploited by malicious users and malicious people to compromise a
vulnerable system.
1) A boundary error within the implementation of the RPCSEC_GSS
authentication type exists in the "svcauth_gss_validate()" function
in src/lib/rpc/svc_auth_gss.c. This can be exploited to cause a
stack-based buffer overflow by sending a specially crafted RPC
message to a vulnerable server.
Successful exploitation potentially allows the execution of arbitrary
code. Products linking to the RPC library may also be affected.
2) The "kadm5_modify_policy_internal()" function in
src/lib/kadm5/srv/svr_policy.c does not correctly check return values
of the "krb5_db_get_policy()" function. This can be exploited to cause
a memory corruption and may potentially allow the execution of
arbitrary code.
Successful exploitation requires valid user credentials and
privileges to modify policies.
Vulnerability #1 is reported in krb5-1.4 through krb5-1.6.2,
vulnerability #2 is reported in krb5-1.5 through krb5-1.6.2.
SOLUTION:
Update to Kerberos 1.5.5 or 1.6.3 as soon as available or apply
patches.
http://web.mit.edu/kerberos/advisories/2007-006-patch.txt
PROVIDED AND/OR DISCOVERED BY:
1) The vendor credits Tenable Network Security, reported via the Zero
Day Initiative.
2) Garrett Wollman, MIT CSAIL.
ORIGINAL ADVISORY:
http://web.mit.edu/kerberos/www/advisories/MITKRB5-SA-2007-006.txt
OTHER REFERENCES:
US-CERT VU#883632:
http://www.kb.cert.org/vuls/id/883632
US-CERT VU#377544:
http://www.kb.cert.org/vuls/id/377544
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About:
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