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I have installed a linux distro and I "think" it is vulnerable to kernel exploits. I have to update kernel but I need to know if it is really compiled in year 2003? How can I know if additional updates are made to the kernel?

Linux gandalf 2.4.21-4.ELsmp #1 SMP Fri Oct 3 17:52:56 EDT 2003 i686 i686 i386 GNU/Linux

Does also "smp" mean that it is safe from latest threats or something? Thank you.

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migrated from Apr 2 '10 at 18:58

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SMP means it supports multi-processors -- see Symmetric multiprocessing.

A 2.4.21 kernel is quite old... according to, the latest version of the 2.4 branch is

And judging from the list of changelogs of the 2.4 branch, it seems it's indeed been released in 2003.

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While the kernel is indeed old, remember that the EL (Enterprise Linux) kernels released by RedHat contain backports of fixes that were in later kernel revisions. In this case, I would doubt there were too many backported fixes to the kernel he was running due to the compile date compared to the release date of the original 2.4.21. – deleted Apr 2 '10 at 19:07

I think you're asking the wrong question here - you want to know whether your kernel has all the security updates you care about. The way you find out is from the kernel's version number, not from when it was built. This isn't necessarily easy if you want to know all the gory details; you'll have to research not only the mainline features/fixes added since 2.4.21 but also the backported fixes in RHEL (mentioned in cd34's comment) which may make up some (but probably not all) of the gap.

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How to know when the kernel was last compiled?

Have you considered just looking at the date of the file? That should be a pretty good indication of the age unless you are doing something weird. I don't think I have ever seen any systems that modify the date of the kernel file to the future.

Typically kernels are stored in /boot but it may also exist as a file named /vmlinuz. Look at your bootloader for exact details.

For the record 2.4.21 is ancient.

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