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CESA-2005:569: zlib security update

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CESA-2005:569: zlib security update



Updated Zlib packages that fix a buffer overflow are now available for Red Hat Enterprise Linux 4. This update has been rated as having important security impact by the Red Hat Security Response Team.

Zlib is a general-purpose lossless data compression library which is used by many different programs. Tavis Ormandy discovered a buffer overflow affecting Zlib version 1.2 and above. An attacker could create a carefully crafted compressed stream that would cause an application to crash if the stream is opened by a user. As an example, an attacker could create a malicious PNG image file which would cause a web browser or mail viewer to crash if the image is viewed. The Common Vulnerabilities and Exposures project assigned the name CAN-2005-2096 to this issue. Please note that the versions of Zlib as shipped with CentOS Linux 2.1 and 3 are not vulnerable to this issue. All users should update to these erratum packages which contain a patch from Mark Adler which corrects this issue.


  • centos-upgrade-zlib
  • centos-upgrade-zlib-devel

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