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On Tue, May 31, 2016, at 10:44, Mick wrote: |
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> On Tuesday 31 May 2016 16:30:27 James wrote: |
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> > Here is an interesting read:: |
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> > |
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> > Security brief: CoreOS Linux Alpha remote SSH issue |
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> > May 19, 2016 · By Matthew Garrett |
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> > |
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> > <snippets> |
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> > |
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> > Gentoo defaults to ending the PAM configuration with an optional pam_permit. |
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> > |
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> > This meant that failing both pam_unix and pam_sss on CoreOS systems would |
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> > surprisingly result in authentication succeeding, and access being granted. |
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> > |
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> > The operator user was not used by CoreOS, but existed because it exists in |
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> > the Gentoo Portage system from which CoreOS is derived. |
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> > <end/snippets> |
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> > |
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> > Full read [1]. It kinda shows that CoreOS is derived from Gentoo |
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> > and not ChromeOS; at least when time to blame a security lapse elsewhere.... |
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> > |
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> > |
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> > enjoy, |
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> > James |
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> > |
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> > [1] https://coreos.com/blog/ |
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> |
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> Does this mean we need to do anything to improve the security of our |
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> systems? |
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|
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The interaction seems to be problematic when SSSD is introduced to the |
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mix, as the SSSD documentation seems to assume a fallthrough to |
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pam_permit.so. With a merely empty user password, I cannot trigger this |
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issue. I will have to try with an expired account and a locked account |
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later. |
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|
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the pam_permit.so line was introduced here: |
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https://gitweb.gentoo.org/proj/pambase.git/commit/?id=ac9023eecfe3c13d212c548bb9d5d1b42a4e044b |
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|
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At the very least, it does seem like it ought to be pam_deny.so instead. |
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|
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I wonder if this issue is still even relevant for Kerberos users? |
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https://bugs.gentoo.org/show_bug.cgi?id=333393 |
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