Several security vulnerability were discovered in the Linux kernel packages, affecting many distributions, including Ubuntu 10.04 LTS, among others.
These are the kernel vulnerabilities found recently in the Linux kernel packages: CVE-2011-1576, CVE-2011-1833, CVE-2011-2494, CVE-2011-2495, CVE-2011-2497, CVE-2011-2695, CVE-2011-2699, CVE-2011-2905, CVE-2011-2928, CVE-2011-3188, and CVE-2011-3191.
You can click on each one to see how it affects your Ubuntu 10.04 LTS system, or go here for an in-depth description. The security flaws can be fixed if you upgrade your system(s) to the linux-image-2.6.32-35 (2.6.32-35.78) package(s).
Don't forget to reboot your computer after the upgrade!
ATTENTION: Due to an unavoidable ABI change, the kernel packages have a new version number, which will force you to reinstall and recompile all third-party kernel modules you might have installed. Moreover, if you use the linux-restricted-modules package, you have to update it as well to get modules which work with the new Linux kernel version.