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-----BEGIN PGP SIGNED MESSAGE----- =========================================================================== AUSCERT External Security Bulletin Redistribution ESB-2001.023 -- RHSA-2001:002-03 glibc local write access vulnerability 17 January 2001 =========================================================================== AusCERT Security Bulletin Summary --------------------------------- Product: glibc Vendor: Red Hat Operating System: Red Hat Linux Linux Impact: Create Arbitrary Files Access Required: Local Ref: ESB-2001.022 - --------------------------BEGIN INCLUDED TEXT-------------------- - --------------------------------------------------------------------- Red Hat, Inc. Red Hat Security Advisory Synopsis: glibc local write access vulnerability Advisory ID: RHSA-2001:002-03 Issue date: 2001-01-15 Updated on: 2001-01-16 Product: Red Hat Linux Keywords: glibc LD_PRELOAD SEGFAULT_OUTPUT_NAME Cross references: Obsoletes: - --------------------------------------------------------------------- 1. Topic: A bug in GNU C Library allows unprivileged user to preload libraries located in /lib or /usr/lib directories into SUID programs even if those libraries have not been marked as such by system administrator. 2. Relevant releases/architectures: Red Hat Linux 6.0 - alpha, i386, sparc, sparcv9 Red Hat Linux 6.1 - alpha, i386, sparc, sparcv9 Red Hat Linux 6.2 - alpha, i386, sparc, sparcv9 3. Problem description: LD_PRELOAD variable is honoured normally even for SUID/SGID applications (but removed afterwards from environment) if it does not contain `/' characters, but there is a special check which only preloads found libraries if they have the SUID bit set. However, if a library has been found in /etc/ld.so.cache, this check was not performed. As a result, a malicious user could preload some /lib or /usr/lib library before SUID/SGID application and create or overwrite a file he did not have permissions to. Also, LD_PROFILE output from SUID programs would go into /var/tmp, making it vulnerable to various link attacks. 4. Solution: For each RPM for your particular architecture, run: rpm -Fvh [filename] where filename is the name of the RPM. 5. Bug IDs fixed (http://bugzilla.redhat.com/bugzilla for more info): 20832 - Unknown system type Nautilus 6. RPMs required: Red Hat Linux 6.0: SRPMS: ftp://updates.redhat.com/6.0/SRPMS/glibc-2.1.3-22.src.rpm ftp://updates.redhat.com/6.0/SRPMS/glibc-2.1.3-22.src.rpm ftp://updates.redhat.com/6.0/SRPMS/glibc-2.1.3-22.src.rpm alpha: ftp://updates.redhat.com/6.0/alpha/glibc-2.1.3-22.alpha.rpm ftp://updates.redhat.com/6.0/alpha/glibc-devel-2.1.3-22.alpha.rpm ftp://updates.redhat.com/6.0/alpha/glibc-profile-2.1.3-22.alpha.rpm ftp://updates.redhat.com/6.0/alpha/nscd-2.1.3-22.alpha.rpm ftp://updates.redhat.com/6.0/alpha/nscd-2.1.3-22.alpha.rpm ftp://updates.redhat.com/6.0/alpha/nscd-2.1.3-22.alpha.rpm i386: ftp://updates.redhat.com/6.0/i386/glibc-2.1.3-22.i386.rpm ftp://updates.redhat.com/6.0/i386/glibc-devel-2.1.3-22.i386.rpm ftp://updates.redhat.com/6.0/i386/glibc-profile-2.1.3-22.i386.rpm ftp://updates.redhat.com/6.0/i386/nscd-2.1.3-22.i386.rpm sparc: ftp://updates.redhat.com/6.0/sparc/glibc-2.1.3-22.sparc.rpm ftp://updates.redhat.com/6.0/sparc/glibc-2.1.3-22.sparc.rpm ftp://updates.redhat.com/6.0/sparc/glibc-devel-2.1.3-22.sparc.rpm ftp://updates.redhat.com/6.0/sparc/glibc-profile-2.1.3-22.sparc.rpm ftp://updates.redhat.com/6.0/sparc/nscd-2.1.3-22.sparc.rpm sparcv9: ftp://updates.redhat.com/6.0/sparcv9/glibc-2.1.3-22.sparcv9.rpm Red Hat Linux 6.1: SRPMS: ftp://updates.redhat.com/6.1/SRPMS/glibc-2.1.3-22.src.rpm alpha: ftp://updates.redhat.com/6.1/alpha/glibc-2.1.3-22.alpha.rpm ftp://updates.redhat.com/6.1/alpha/glibc-devel-2.1.3-22.alpha.rpm ftp://updates.redhat.com/6.1/alpha/glibc-profile-2.1.3-22.alpha.rpm ftp://updates.redhat.com/6.1/alpha/nscd-2.1.3-22.alpha.rpm i386: ftp://updates.redhat.com/6.1/i386/glibc-2.1.3-22.i386.rpm ftp://updates.redhat.com/6.1/i386/glibc-devel-2.1.3-22.i386.rpm ftp://updates.redhat.com/6.1/i386/glibc-profile-2.1.3-22.i386.rpm ftp://updates.redhat.com/6.1/i386/nscd-2.1.3-22.i386.rpm ftp://updates.redhat.com/6.1/i386/nscd-2.1.3-22.i386.rpm ftp://updates.redhat.com/6.1/i386/nscd-2.1.3-22.i386.rpm sparc: ftp://updates.redhat.com/6.1/sparc/glibc-2.1.3-22.sparc.rpm ftp://updates.redhat.com/6.1/sparc/glibc-2.1.3-22.sparc.rpm ftp://updates.redhat.com/6.1/sparc/glibc-devel-2.1.3-22.sparc.rpm ftp://updates.redhat.com/6.1/sparc/glibc-profile-2.1.3-22.sparc.rpm ftp://updates.redhat.com/6.1/sparc/glibc-profile-2.1.3-22.sparc.rpm ftp://updates.redhat.com/6.1/sparc/glibc-profile-2.1.3-22.sparc.rpm ftp://updates.redhat.com/6.1/sparc/nscd-2.1.3-22.sparc.rpm sparcv9: ftp://updates.redhat.com/6.1/sparcv9/glibc-2.1.3-22.sparcv9.rpm Red Hat Linux 6.2: SRPMS: ftp://updates.redhat.com/6.2/SRPMS/glibc-2.1.3-22.src.rpm alpha: ftp://updates.redhat.com/6.2/alpha/glibc-2.1.3-22.alpha.rpm ftp://updates.redhat.com/6.2/alpha/glibc-devel-2.1.3-22.alpha.rpm ftp://updates.redhat.com/6.2/alpha/glibc-profile-2.1.3-22.alpha.rpm ftp://updates.redhat.com/6.2/alpha/nscd-2.1.3-22.alpha.rpm i386: ftp://updates.redhat.com/6.2/i386/glibc-2.1.3-22.i386.rpm ftp://updates.redhat.com/6.2/i386/glibc-devel-2.1.3-22.i386.rpm ftp://updates.redhat.com/6.2/i386/glibc-profile-2.1.3-22.i386.rpm ftp://updates.redhat.com/6.2/i386/nscd-2.1.3-22.i386.rpm ftp://updates.redhat.com/6.2/i386/nscd-2.1.3-22.i386.rpm ftp://updates.redhat.com/6.2/i386/nscd-2.1.3-22.i386.rpm sparc: ftp://updates.redhat.com/6.2/sparc/glibc-2.1.3-22.sparc.rpm ftp://updates.redhat.com/6.2/sparc/glibc-2.1.3-22.sparc.rpm ftp://updates.redhat.com/6.2/sparc/glibc-2.1.3-22.sparc.rpm ftp://updates.redhat.com/6.2/sparc/glibc-2.1.3-22.sparc.rpm ftp://updates.redhat.com/6.2/sparc/glibc-devel-2.1.3-22.sparc.rpm ftp://updates.redhat.com/6.2/sparc/glibc-devel-2.1.3-22.sparc.rpm ftp://updates.redhat.com/6.2/sparc/glibc-devel-2.1.3-22.sparc.rpm ftp://updates.redhat.com/6.2/sparc/glibc-profile-2.1.3-22.sparc.rpm ftp://updates.redhat.com/6.2/sparc/nscd-2.1.3-22.sparc.rpm sparcv9: ftp://updates.redhat.com/6.2/sparcv9/glibc-2.1.3-22.sparcv9.rpm 7. Verification: MD5 sum Package Name - -------------------------------------------------------------------------- ef78f44366467486a0dac8794bc17ab9 6.2/SRPMS/glibc-2.1.3-22.src.rpm b860e2f939f4e6517f4672361d746b38 6.2/i386/nscd-2.1.3-22.i386.rpm e9b9b581fa4eda1a9aa2a5de8b267889 6.2/i386/glibc-profile-2.1.3-22.i386.rpm 2a779a3f6c3b87059cf40686f55dc2f6 6.2/i386/glibc-devel-2.1.3-22.i386.rpm b841df797bf42585476f30b1ba489e30 6.2/i386/glibc-2.1.3-22.i386.rpm e768b72385324280d62b271895261021 6.2/alpha/nscd-2.1.3-22.alpha.rpm 57040728348767ef4475ab82091a3db0 6.2/alpha/glibc-profile-2.1.3-22.alpha.rpm e5a7cf85e50c599a51e7b9ee7d1bc78d 6.2/alpha/glibc-devel-2.1.3-22.alpha.rpm c1edf134c6d5790ce74d7c4272ec8687 6.2/alpha/glibc-2.1.3-22.alpha.rpm 1de8f29192f62e1cc33f76d920e20a1a 6.2/sparcv9/glibc-2.1.3-22.sparcv9.rpm 966d69ca5182a97315e1f7bf5a5b7c30 6.2/sparc/nscd-2.1.3-22.sparc.rpm a611d30013f4f98576aebb58b906c6db 6.2/sparc/glibc-profile-2.1.3-22.sparc.rpm a305bcbf7e6f273c0c9759b622b04509 6.2/sparc/glibc-devel-2.1.3-22.sparc.rpm 74ae10e642a463b053ef531048410330 6.2/sparc/glibc-2.1.3-22.sparc.rpm ef78f44366467486a0dac8794bc17ab9 6.1/SRPMS/glibc-2.1.3-22.src.rpm e768b72385324280d62b271895261021 6.1/alpha/nscd-2.1.3-22.alpha.rpm 57040728348767ef4475ab82091a3db0 6.1/alpha/glibc-profile-2.1.3-22.alpha.rpm e5a7cf85e50c599a51e7b9ee7d1bc78d 6.1/alpha/glibc-devel-2.1.3-22.alpha.rpm c1edf134c6d5790ce74d7c4272ec8687 6.1/alpha/glibc-2.1.3-22.alpha.rpm 1de8f29192f62e1cc33f76d920e20a1a 6.1/sparcv9/glibc-2.1.3-22.sparcv9.rpm 966d69ca5182a97315e1f7bf5a5b7c30 6.1/sparc/nscd-2.1.3-22.sparc.rpm a611d30013f4f98576aebb58b906c6db 6.1/sparc/glibc-profile-2.1.3-22.sparc.rpm a305bcbf7e6f273c0c9759b622b04509 6.1/sparc/glibc-devel-2.1.3-22.sparc.rpm 74ae10e642a463b053ef531048410330 6.1/sparc/glibc-2.1.3-22.sparc.rpm b860e2f939f4e6517f4672361d746b38 6.1/i386/nscd-2.1.3-22.i386.rpm e9b9b581fa4eda1a9aa2a5de8b267889 6.1/i386/glibc-profile-2.1.3-22.i386.rpm 2a779a3f6c3b87059cf40686f55dc2f6 6.1/i386/glibc-devel-2.1.3-22.i386.rpm b841df797bf42585476f30b1ba489e30 6.1/i386/glibc-2.1.3-22.i386.rpm ef78f44366467486a0dac8794bc17ab9 6.0/SRPMS/glibc-2.1.3-22.src.rpm 1de8f29192f62e1cc33f76d920e20a1a 6.0/sparcv9/glibc-2.1.3-22.sparcv9.rpm 966d69ca5182a97315e1f7bf5a5b7c30 6.0/sparc/nscd-2.1.3-22.sparc.rpm a611d30013f4f98576aebb58b906c6db 6.0/sparc/glibc-profile-2.1.3-22.sparc.rpm a305bcbf7e6f273c0c9759b622b04509 6.0/sparc/glibc-devel-2.1.3-22.sparc.rpm 74ae10e642a463b053ef531048410330 6.0/sparc/glibc-2.1.3-22.sparc.rpm b860e2f939f4e6517f4672361d746b38 6.0/i386/nscd-2.1.3-22.i386.rpm e9b9b581fa4eda1a9aa2a5de8b267889 6.0/i386/glibc-profile-2.1.3-22.i386.rpm 2a779a3f6c3b87059cf40686f55dc2f6 6.0/i386/glibc-devel-2.1.3-22.i386.rpm b841df797bf42585476f30b1ba489e30 6.0/i386/glibc-2.1.3-22.i386.rpm e768b72385324280d62b271895261021 6.0/alpha/nscd-2.1.3-22.alpha.rpm 57040728348767ef4475ab82091a3db0 6.0/alpha/glibc-profile-2.1.3-22.alpha.rpm e5a7cf85e50c599a51e7b9ee7d1bc78d 6.0/alpha/glibc-devel-2.1.3-22.alpha.rpm c1edf134c6d5790ce74d7c4272ec8687 6.0/alpha/glibc-2.1.3-22.alpha.rpm These packages are GPG signed by Red Hat, Inc. for security. Our key is available at: http://www.redhat.com/corp/contact.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> 8. References: Copyright(c) 2000, 2001 Red Hat, Inc. - --------------------------END INCLUDED TEXT-------------------- This security bulletin is provided as a service to AusCERT's members. As AusCERT did not write the document quoted above, AusCERT has had no control over its content. The decision to use any or all of this information is the responsibility of each user or organisation, and should be done so in accordance with site policies and procedures. NOTE: This is only the original release of the security bulletin. It may not be updated when updates to the original are made. If downloading at a later date, it is recommended that the bulletin is retrieved directly from the original authors to ensure that the information is still current. Contact information for the authors of the original document is included in the Security Bulletin above. If you have any questions or need further information, please contact them directly. Previous advisories and external security bulletins can be retrieved from: http://www.auscert.org.au/Information/advisories.html If you believe that your system has been compromised, contact AusCERT or your representative in FIRST (Forum of Incident Response and Security Teams). Internet Email: auscert@auscert.org.au Facsimile: (07) 3365 7031 Telephone: (07) 3365 4417 (International: +61 7 3365 4417) AusCERT personnel answer during Queensland business hours which are GMT+10:00 (AEST). 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