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-----BEGIN PGP SIGNED MESSAGE----- =========================================================================== AUSCERT External Security Bulletin Redistribution ESB-2002.561 -- RHSA-2002:175-16 Updated nss_ldap packages fix buffer overflow 09 October 2002 =========================================================================== AusCERT Security Bulletin Summary --------------------------------- Product: nss_ldap Vendor: Red Hat Operating System: Red Hat Linux 6.2 Red Hat Linux 7.0 Red Hat Linux 7.1 Red Hat Linux 7.2 Red Hat Linux 7.3 Platform: Alpha i386 IA-64 SPARC Impact: Execute Arbitrary Code/Commands Denial of Service Access Required: Remote Ref: ESB-2002.263 - --------------------------BEGIN INCLUDED TEXT-------------------- - --------------------------------------------------------------------- Red Hat, Inc. Red Hat Security Advisory Synopsis: Updated nss_ldap packages fix buffer overflow Advisory ID: RHSA-2002:175-16 Issue date: 2002-08-12 Updated on: 2002-10-03 Product: Red Hat Linux Keywords: nss_ldap dns automatic configuration MAXPACKET Cross references: Obsoletes: RHSA-2002:084 CVE Names: CAN-2002-0825 CAN-2002-0374 - --------------------------------------------------------------------- 1. Topic: Updated nss_ldap packages are now available for Red Hat Linux 6.2, 7, 7.1, 7.2, and 7.3. These updates fix a potential buffer overflow which can occur when nss_ldap is set to configure itself using information stored in DNS, a format string bug in logging functions used in pam_ldap, and to properly handle truncated DNS responses. 2. Relevant releases/architectures: Red Hat Linux 6.2 - alpha, i386, sparc Red Hat Linux 7.0 - alpha, i386 Red Hat Linux 7.1 - alpha, i386, ia64 Red Hat Linux 7.2 - i386, ia64 Red Hat Linux 7.3 - i386 3. Problem description: nss_ldap is a set of C library extensions that allow X.500 and LDAP directory servers to be used as a primary source of aliases, ethers, groups, hosts, networks, protocols, users, RPCs, services, and shadow passwords (instead of or in addition to using flat files or NIS). When versions of nss_ldap prior to nss_ldap-198 are configured without a value for the "host" setting, nss_ldap will attempt to configure itself by using SRV records stored in DNS. When parsing the results of the DNS query, nss_ldap does not check that the data returned by the server will fit into an internal buffer, leaving it vulnerable to a buffer overflow. The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CAN-2002-0825 to this issue. When versions of nss_ldap prior to nss_ldap-199 are configured without a value for the "host" setting, nss_ldap will attempt to configure itself by using SRV records stored in DNS. When parsing the results of the DNS query, nss_ldap does not check that the data returned has not been truncated by the resolver libraries to avoid a buffer overflow, and may attempt to parse more data than is actually available, leaving it vulnerable to a read buffer overflow. Versions of pam_ldap prior to version 144 include a format string bug in the logging function. The packages included in this erratum update pam_ldap to version 144, fixing this bug. The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CAN-2002-0374 to this issue. All users of nss_ldap should update to these errata packages which are not vulnerable to the above issues. The errata packages are based on nss_ldap-189 with the addition of a backported security patch and pam_ldap version 144. Thanks to the nss_ldap and pam_ldap team at padl.com for providing information about these issues. 4. Solution: Before applying this update, make sure all previously released errata relevant to your system have been applied. To update all RPMs for your particular architecture, run: rpm -Fvh [filenames] where [filenames] is a list of the RPMs you wish to upgrade. Only those RPMs which are currently installed will be updated. Those RPMs which are not installed but included in the list will not be updated. Note that you can also use wildcards (*.rpm) if your current directory *only* contains the desired RPMs. Please note that this update is also available via Red Hat Network. Many people find this an easier way to apply updates. To use Red Hat Network, launch the Red Hat Update Agent with the following command: up2date This will start an interactive process that will result in the appropriate RPMs being upgraded on your system. 5. RPMs required: Red Hat Linux 6.2: SRPMS: ftp://updates.redhat.com/6.2/en/os/SRPMS/nss_ldap-189-3.6.src.rpm alpha: ftp://updates.redhat.com/6.2/en/os/alpha/nss_ldap-189-3.6.alpha.rpm i386: ftp://updates.redhat.com/6.2/en/os/i386/nss_ldap-189-3.6.i386.rpm sparc: ftp://updates.redhat.com/6.2/en/os/sparc/nss_ldap-189-3.6.sparc.rpm Red Hat Linux 7.0: SRPMS: ftp://updates.redhat.com/7.0/en/os/SRPMS/nss_ldap-189-3.7.src.rpm alpha: ftp://updates.redhat.com/7.0/en/os/alpha/nss_ldap-189-3.7.alpha.rpm i386: ftp://updates.redhat.com/7.0/en/os/i386/nss_ldap-189-3.7.i386.rpm Red Hat Linux 7.1: SRPMS: ftp://updates.redhat.com/7.1/en/os/SRPMS/nss_ldap-189-3.7.src.rpm alpha: ftp://updates.redhat.com/7.1/en/os/alpha/nss_ldap-189-3.7.alpha.rpm i386: ftp://updates.redhat.com/7.1/en/os/i386/nss_ldap-189-3.7.i386.rpm ia64: ftp://updates.redhat.com/7.1/en/os/ia64/nss_ldap-189-3.7.ia64.rpm Red Hat Linux 7.2: SRPMS: ftp://updates.redhat.com/7.2/en/os/SRPMS/nss_ldap-189-4.src.rpm i386: ftp://updates.redhat.com/7.2/en/os/i386/nss_ldap-189-4.i386.rpm ia64: ftp://updates.redhat.com/7.2/en/os/ia64/nss_ldap-189-4.ia64.rpm Red Hat Linux 7.3: SRPMS: ftp://updates.redhat.com/7.3/en/os/SRPMS/nss_ldap-189-4.src.rpm i386: ftp://updates.redhat.com/7.3/en/os/i386/nss_ldap-189-4.i386.rpm 6. Verification: MD5 sum Package Name - -------------------------------------------------------------------------- 2acbcd575035a1afcb9e74694a6b7b39 6.2/en/os/SRPMS/nss_ldap-189-3.6.src.rpm 1a670c4c2a343b26508aa04ae06d2306 6.2/en/os/alpha/nss_ldap-189-3.6.alpha.rpm 4069002846304df7840cbe81517f8b3d 6.2/en/os/i386/nss_ldap-189-3.6.i386.rpm e26b1be702d0bf65f455e17d16844354 6.2/en/os/sparc/nss_ldap-189-3.6.sparc.rpm 9b44c5148cd1d3d688a9603f11a4d794 7.0/en/os/SRPMS/nss_ldap-189-3.7.src.rpm 2d245d41c6a27b62670a0e3cbc48e93b 7.0/en/os/alpha/nss_ldap-189-3.7.alpha.rpm 5c34d52cfa0425e8b3d0e63838729703 7.0/en/os/i386/nss_ldap-189-3.7.i386.rpm 9b44c5148cd1d3d688a9603f11a4d794 7.1/en/os/SRPMS/nss_ldap-189-3.7.src.rpm 2d245d41c6a27b62670a0e3cbc48e93b 7.1/en/os/alpha/nss_ldap-189-3.7.alpha.rpm 5c34d52cfa0425e8b3d0e63838729703 7.1/en/os/i386/nss_ldap-189-3.7.i386.rpm 27c07eb113adebc7d79d48d8c9df9356 7.1/en/os/ia64/nss_ldap-189-3.7.ia64.rpm d421772f8f5bd985dc2c288aee729ff6 7.2/en/os/SRPMS/nss_ldap-189-4.src.rpm 8dc0d40503cbc09a55a111fc53ec42ba 7.2/en/os/i386/nss_ldap-189-4.i386.rpm acd545a47e2be38ed8c9b94ea9801e4c 7.2/en/os/ia64/nss_ldap-189-4.ia64.rpm d421772f8f5bd985dc2c288aee729ff6 7.3/en/os/SRPMS/nss_ldap-189-4.src.rpm 8dc0d40503cbc09a55a111fc53ec42ba 7.3/en/os/i386/nss_ldap-189-4.i386.rpm These packages are GPG signed by Red Hat, Inc. for security. Our key is available at: http://www.redhat.com/about/contact/pgpkey.html You can verify each package with the following command: rpm --checksig <filename> If you only wish to verify that each package has not been corrupted or tampered with, examine only the md5sum with the following command: rpm --checksig --nogpg <filename> 7. References: http://www.padl.com/Articles/PotentialBufferOverflowin.html http://www.padl.com/OSS/pam_ldap.html http://archives.neohapsis.com/archives/vulnwatch/2002-q2/0053.html http://www.kb.cert.org/vuls/id/738331 http://cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-2002-0825 http://cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-2002-0374 Copyright(c) 2000, 2001, 2002 Red Hat, Inc. - --------------------------END INCLUDED TEXT-------------------- You have received this e-mail bulletin as a result of your organisation's registration with AusCERT. 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