Openwall GNU/*/Linux - a small security-enhanced Linux distro for servers
[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Date: Sun, 1 May 2016 07:43:04 +0200
From: Salvatore Bonaccorso <carnil@...ian.org>
To: OSS Security Mailinglist <oss-security@...ts.openwall.com>
Subject: CVE Request: libpam-sshauth: local root privilege escalation

Hi

Due to a programming error, libpam-sshauth returned PAM_SUCCESS where
it should fail with PAM_AUTH_ERR. This was fixed in Debian in the last
upload to unstable with the attached patch.

Introduced with:
https://bazaar.launchpad.net/~ltsp-upstream/ltsp/libpam-sshauth/revision/93/src/pam_sshauth.c
Fixed by:
https://bazaar.launchpad.net/~ltsp-upstream/ltsp/libpam-sshauth/revision/114

Could you assign a CVE for this issue?

Regards,
Salvatore

Return PAM_AUTH_ERR when a system user. This prevents the pam module
from returning success without asking for authentication credentials!

diff --git a/src/pam_sshauth.c b/src/pam_sshauth.c
index 939ea79..879c9e5 100644
--- a/src/pam_sshauth.c
+++ b/src/pam_sshauth.c
@@ -101,7 +100,7 @@ pam_sm_authenticate (pam_handle_t * pamh, int flags, int argc,
     }
 
   /*
-   * Is it a system user?  Succeed.
+   * Is it a system user?  Fail.
    */
 
   pam_debug (pamh, "username %s", username);
@@ -110,7 +109,7 @@ pam_sm_authenticate (pam_handle_t * pamh, int flags, int argc,
     {
       if (pwent->pw_uid < UID_MIN)
         {
-          return PAM_SUCCESS;
+          return PAM_AUTH_ERR;
         }
     }
 

Powered by blists - more mailing lists

Your e-mail address:

Please check out the Open Source Software Security Wiki, which is counterpart to this mailing list.

Powered by Openwall GNU/*/Linux - Powered by OpenVZ