Integer signedness error in the _pam_StrTok function in libpam/pam_misc.c in Linux-PAM (aka pam) 1.0.3 and earlier, when a configuration file contains non-ASCII usernames, might allow remote attackers to cause a denial of service, and might allow remote authenticated users to obtain login access with a different user's non-ASCII username, via a login attempt.

USN-1140-1 fixed vulnerabilities in PAM. A regression was found that caused cron to stop working with a 'Module is unknown' error. As a result, systems configured with automatic updates will not receive updates until cron is restarted, these updates are installed or the system is rebooted. This update fixes the problem.

We apologize for the inconvenience.

Marcus Granado discovered that PAM incorrectly handled configuration files with non-ASCII usernames. A remote attacker could use this flaw to cause a denial of service, or possibly obtain login access with a different users username. This issue only affected Ubuntu 8.04 LTS.
(CVE-2009-0887)

It was discovered that the PAM pam_xauth, pam_env and pam_mail modules incorrectly handled dropping privileges when performing operations. A local attacker could use this flaw to read certain arbitrary files, and access other sensitive information. (CVE-2010-3316, CVE-2010-3430, CVE-2010-3431, CVE-2010-3435)

It was discovered that the PAM pam_namespace module incorrectly cleaned the environment during execution of the namespace.init script. A local attacker could use this flaw to possibly gain privileges. (CVE-2010-3853)

It was discovered that the PAM pam_xauth module incorrectly handled certain failures. A local attacker could use this flaw to delete certain unintended files. (CVE-2010-4706)

It was discovered that the PAM pam_xauth module incorrectly verified certain file properties. A local attacker could use this flaw to cause a denial of service. (CVE-2010-4707).

Note that Tenable Network Security has extracted the preceding description block directly from the Ubuntu security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

Marcus Granado discovered that PAM incorrectly handled configuration files with non-ASCII usernames. A remote attacker could use this flaw to cause a denial of service, or possibly obtain login access with a different users username. This issue only affected Ubuntu 8.04 LTS.
(CVE-2009-0887)

It was discovered that the PAM pam_xauth, pam_env and pam_mail modules incorrectly handled dropping privileges when performing operations. A local attacker could use this flaw to read certain arbitrary files, and access other sensitive information. (CVE-2010-3316, CVE-2010-3430, CVE-2010-3431, CVE-2010-3435)

It was discovered that the PAM pam_namespace module incorrectly cleaned the environment during execution of the namespace.init script.
A local attacker could use this flaw to possibly gain privileges.
(CVE-2010-3853)

It was discovered that the PAM pam_xauth module incorrectly handled certain failures. A local attacker could use this flaw to delete certain unintended files. (CVE-2010-4706)

It was discovered that the PAM pam_xauth module incorrectly verified certain file properties. A local attacker could use this flaw to cause a denial of service. (CVE-2010-4707).

Note that Tenable Network Security has extracted the preceding description block directly from the Ubuntu security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

The remote host is affected by the vulnerability described in GLSA-200909-01 (Linux-PAM: Privilege escalation)

    Marcus Granado repoted that Linux-PAM does not properly handle user     names that contain Unicode characters. This is related to integer     signedness errors in the pam_StrTok() function in libpam/pam_misc.c.
  Impact :

    A remote attacker could exploit this vulnerability to cause a Denial of     Service. A remote authenticated attacker could exploit this     vulnerability to log in to a system with the account of a user that has     a similar user name, but with non-ASCII characters.
  Workaround :

    There is no known workaround at this time.

Update to new minor upstream release. Minor security issue fixes and bug fixes.

Note that Tenable Network Security has extracted the preceding description block directly from the Fedora security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

A security vulnerability has been identified and fixed in pam :

Integer signedness error in the _pam_StrTok function in libpam/pam_misc.c in Linux-PAM (aka pam) 1.0.3 and earlier, when a configuration file contains non-ASCII usernames, might allow remote attackers to cause a denial of service, and might allow remote authenticated users to obtain login access with a different user's non-ASCII username, via a login attempt (CVE-2009-0887).

The updated packages have been patched to prevent this.

Additionally some development packages were missing that are required to build pam for CS4, these are also provided with this update.

ID	Name	Product	Family	Severity
55103	Ubuntu 8.04 LTS / 10.04 LTS / 10.10 / 11.04 : pam regression (USN-1140-2)	Nessus	Ubuntu Local Security Checks	medium
55102	Ubuntu 8.04 LTS / 10.04 LTS / 10.10 / 11.04 : pam vulnerabilities (USN-1140-1)	Nessus	Ubuntu Local Security Checks	medium
40879	GLSA-200909-01 : Linux-PAM: Privilege escalation	Nessus	Gentoo Local Security Checks	medium
37813	Fedora 10 : pam-1.0.4-4.fc10 (2009-3204)	Nessus	Fedora Local Security Checks	medium
36591	Mandriva Linux Security Advisory : pam (MDVSA-2009:077)	Nessus	Mandriva Local Security Checks	medium
36156	Fedora 9 : pam-1.0.4-4.fc9 (2009-3231)	Nessus	Fedora Local Security Checks	medium

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CVE-2009-0887

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