--------------------------------------------------------------------- Red Hat Security Advisory Synopsis: Updated stunnel packages fix signal vulnerability Advisory ID: RHSA-2003:221-01 Issue date: 2003-07-25 Updated on: 2003-07-25 Product: Red Hat Linux Keywords: stunnel signal handler reentrancy DoS Cross references: Obsoletes: RHSA-2002:002 CVE Names: CAN-2002-1563 --------------------------------------------------------------------- 1. Topic: Updated stunnel packages are now available for Red Hat Linux 7.1, 7.2, 7.3, and 8.0. These updates correct a potential vulnerability in stunnel's signal handling. 2. Relevant releases/architectures: Red Hat Linux 7.1 - i386 Red Hat Linux 7.2 - i386, ia64 Red Hat Linux 7.3 - i386 Red Hat Linux 8.0 - i386 3. Problem description: Stunnel is a wrapper for network connections. It can be used to tunnel an unencrypted network connection over a secure connection (encrypted using SSL or TLS) or to provide a secure means of connecting to services that do not natively support encryption. When configured to listen for incoming connections (instead of being invoked by xinetd), stunnel can be configured to either start a thread or a child process to handle each new connection. If Stunnel is configured to start a new child process to handle each connection, it will receive a SIGCHLD signal when that child exits. Stunnel versions prior to 4.04 would perform tasks in the SIGCHLD signal handler which, if interrupted by another SIGCHLD signal, could be unsafe. This could lead to a denial of service. All users are urged to upgrade to these errata packages, which modify stunnel's signal handler so that it is not vulnerable to this issue. NOTE: After upgrading, any instances of stunnel configured to run in daemon mode should be restarted, and any active network connections that are currently being serviced by stunnel should be terminated and reestablished. 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. Bug IDs fixed (http://bugzilla.redhat.com/bugzilla for more info): 82325 - stunnel security errata required
*** This bug has been marked as a duplicate of 26175 ***