The png_check_keyword function in pngwutil.c in libpng before 1.0.42, and 1.2.x before 1.2.34, might allow context-dependent attackers to set the value of an arbitrary memory location to zero via vectors involving creation of crafted PNG files with keywords, related to an implicit cast of the '\0' character constant to a NULL pointer. NOTE: some sources incorrectly report this as a double free vulnerability.
WIND00152457.zip is for 1.4
WIND00152460.zip is for 1.5
1. Unzip the patch under [install_dir]/updates
2. Install the patch CD by entering the patch CD directory and run setup_linux.
3. This is a source only patch so you will have to build the kernel
4. Issue a make fs and make the kernel in a configured directory.
5. Upload the kernel and rootfs into the target and boot it up.