Heads up: PAM 1.5.0 has a auth bypass under some conditions

                							

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Heads up: PAM 1.5.0 has a auth bypass under some conditions

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From: Marcus Meissner &lt;meissner () suse de&gt;

Date: Tue, 24 Nov 2020 19:20:21 +0100

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Hi,

(via IRC, spotted by Foxboron)

PAM 1.5.0 had a potential auth bypass, if a user did not exist and the root password was
empty (but root locked down).

The reporters usecase was spammers pretending to be unknown users with a PAM enabled dovecot.

This issue affected only pam 1.5.0.

News entry:
https://github.com/linux-pam/linux-pam/commit/28b8c7045ac8ea4ea080bce02a2df9e3b9e98f06

CVE-2020-27780

github issue reporting the problem: https://github.com/linux-pam/linux-pam/issues/284
Fixing commit: https://github.com/linux-pam/linux-pam/commit/af0faf666c5008e54dfe43684f210e3581ff1bca

Ciao, Marcus

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Current thread:

Heads up: PAM 1.5.0 has a auth bypass under some conditions Marcus Meissner (Nov 24)

Re: Heads up: PAM 1.5.0 has a auth bypass under some conditions John Helmert III (Nov 24)

Re: Heads up: PAM 1.5.0 has a auth bypass under some conditions Érico Nogueira (Nov 24)

Re: Heads up: PAM 1.5.0 has a auth bypass under some conditions Dmitry V. Levin (Nov 24)

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