Date: Mon, 18 Sep 2000 15:42:00 -0400 From: bugzilla@REDHAT.COM Subject: [RHSA-2000:061-02] syslog format vulnerability in klogd To: BUGTRAQ@SECURITYFOCUS.COM --------------------------------------------------------------------- Red Hat, Inc. Security Advisory Synopsis: syslog format vulnerability in klogd Advisory ID: RHSA-2000:061-02 Issue date: 2000-09-18 Updated on: 2000-09-18 Product: Red Hat Linux Keywords: syslog format string klogd syslogd Cross references: N/A --------------------------------------------------------------------- 1. Topic: Various vulnerabilities exist in syslogd/klogd. By exploiting these vulnerabilities, it could be possible for local users to gain root access. No remote exploit exists at this time, but it remains theoretically possible that this vulnerability could be exploited remotely under certain rare circumstances. All users should upgrade to the new sysklogd packages. Users of Red Hat Linux 6.0 and 6.1 should use the packages for Red Hat Linux 6.2. 2. Relevant releases/architectures: Red Hat Linux 5.2 - i386, alpha, sparc Red Hat Linux 6.0 - i386, alpha, sparc Red Hat Linux 6.1 - i386, alpha, sparc Red Hat Linux 6.2 - i386, alpha, sparc 3. Problem description: klogd contains instances of the: syslog( LOG_INFO, buffer ); vulnerability that has been recently been discussed on Bugtraq and similar mailing lists; by supplying some string that contains '%' escapes, it is possible to have those escapes interpreted, which can lead to the ability to gain root access. Also, there are a couple of minor buffer overflow/termination problems that could allow local users to crash syslogd and cause bogus messages to be printed on the local system console. The updated sysklogd packages fix these vulnerabilities/issues. 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): N/A 6. RPMs required: Red Hat Linux 5.2: sparc: ftp://updates.redhat.com/5.2/sparc/sysklogd-1.3.31-1.6.sparc.rpm alpha: ftp://updates.redhat.com/5.2/alpha/sysklogd-1.3.31-1.6.alpha.rpm i386: ftp://updates.redhat.com/5.2/i386/sysklogd-1.3.31-1.6.i386.rpm sources: ftp://updates.redhat.com/5.2/SRPMS/sysklogd-1.3.31-1.6.src.rpm Red Hat Linux 6.2: sparc: ftp://updates.redhat.com/6.2/sparc/sysklogd-1.3.31-17.sparc.rpm i386: ftp://updates.redhat.com/6.2/i386/sysklogd-1.3.31-17.i386.rpm alpha: ftp://updates.redhat.com/6.2/alpha/sysklogd-1.3.31-17.alpha.rpm sources: ftp://updates.redhat.com/6.2/SRPMS/sysklogd-1.3.31-17.src.rpm 7. Verification: MD5 sum Package Name -------------------------------------------------------------------------- cd92613fc9a7409a90f6ff774e6e85d7 5.2/SRPMS/sysklogd-1.3.31-1.6.src.rpm c7c44b7a38f4518daecca77cf7d45ba8 5.2/alpha/sysklogd-1.3.31-1.6.alpha.rpm f100359030451c4be9b3bd99c3ec73a1 5.2/i386/sysklogd-1.3.31-1.6.i386.rpm 1c7f004ca29c966e0a03896f239d1317 5.2/sparc/sysklogd-1.3.31-1.6.sparc.rpm 69d50a8a9d490598fc11eef40fdf4552 6.2/SRPMS/sysklogd-1.3.31-17.src.rpm 2a7e2c7848d1f2d9607f3e6e3702cf2e 6.2/alpha/sysklogd-1.3.31-17.alpha.rpm 287d5022aa9d1a6ba9e03c51acc85229 6.2/i386/sysklogd-1.3.31-17.i386.rpm 150a05567dd4d626326028b1ac31f34d 6.2/sparc/sysklogd-1.3.31-17.sparc.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: Thanks go to Jouko Pynnonen, Solar Designer, and Daniel Jacobowitz for discovering the vulnerabilities and providing patches. Copyright(c) 2000 Red Hat, Inc.