CVE-2011-4079: Buffer Overflow
A bug in slapd's UTF8StringNormalize() function can cause a one-byte buffer overflow when it is passed a zero-length string. The code then writes a '\0' past the one-byte long buffer allocated on the heap, which could possibly allow a remote authenticated user to crash slapd. As per the upstream report [1], this bug has been present since 2003-04-07 [2] so should affect all versions of openldap we currently ship.
A patch to correct the flaw has been committed [3] (depends on the previous patch [4]).
[1] http://www.openldap.org/its/index.cgi/Software%20Bugs?id=7059;selectid=7059 [2] http://www.openldap.org/devel/gitweb.cgi?p=openldap.git;a=commitdiff;h=67d6b23d [3] http://www.openldap.org/devel/gitweb.cgi?p=openldap.git;a=commitdiff;h=507238713b71208ec4f262f312cb495a302df9e9 [4] http://www.openldap.org/devel/gitweb.cgi?p=openldap.git;a=commitdiff;h=d0dd8616f1c68a868afeb8c2c5c09969e366e2c0
Other sources
Off-by-one error in the UTF8StringNormalize function in OpenLDAP 2.4.26 and earlier allows remote attackers to cause a denial of service (slapd crash) via a zero-length string that triggers a heap-based buffer overflow, as demonstrated using an empty postalAddressAttribute value in an LDIF entry.
— MITRE
Affected Software
Remediation
Patch Available
Event History
Frequently Asked Questions
What is the severity of CVE-2011-4079?
The severity of CVE-2011-4079 is classified as high due to the potential for crashing the OpenLDAP server.
How do I fix CVE-2011-4079?
Fix CVE-2011-4079 by upgrading to a patched version of OpenLDAP that resolves the buffer overflow vulnerability.
Who is affected by CVE-2011-4079?
CVE-2011-4079 affects certain versions of OpenLDAP including releases from 1.0 to 2.4.26.
What is the impact of CVE-2011-4079 on affected systems?
The impact of CVE-2011-4079 can lead to a crash of the OpenLDAP server when an authenticated user sends a zero-length string.
Is CVE-2011-4079 targeted at remote users?
Yes, CVE-2011-4079 can be exploited by remote authenticated users to trigger the vulnerability.