Multiple CRLF injection vulnerabilities in (1) chfn and (2) chsh in shadow 1:4.1.4 allow local users to add new users or groups to /etc/passwd via the GECOS field.

The remote host is affected by the vulnerability described in GLSA-201412-09 (Multiple packages, Multiple vulnerabilities fixed in 2011)

    Vulnerabilities have been discovered in the packages listed below.
      Please review the CVE identifiers in the Reference section for details.
      FMOD Studio       PEAR Mail       LVM2       GnuCash       xine-lib       Last.fm Scrobbler       WebKitGTK+       shadow tool suite       PEAR       unixODBC       Resource Agents       mrouted       rsync       XML Security Library       xrdb       Vino       OProfile       syslog-ng       sFlow Toolkit       GNOME Display Manager       libsoup       CA Certificates       Gitolite       QtCreator       Racer   Impact :

    A context-dependent attacker may be able to gain escalated privileges,       execute arbitrary code, cause Denial of Service, obtain sensitive       information, or otherwise bypass security restrictions.
  Workaround :

    There are no known workarounds at this time.

New shadow packages are available for Slackware 13.1 and -current to fix a security issue.

Kees Cook discovered that the chfn and chsh utilities do not properly sanitize user input that includes newlines. An attacker could use this to corrupt passwd entries and may create users or groups in NIS environments.

Packages in the oldstable distribution (lenny) are not affected by this problem.

Kees Cook discovered that some shadow utilities did not correctly validate user input. A local attacker could exploit this flaw to inject newlines into the /etc/passwd file. If the system was configured to use NIS, this could lead to existing NIS groups or users gaining or losing access to the system, resulting in a denial of service or unauthorized access.

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.

ID	Name	Product	Family	Severity
79962	GLSA-201412-09 : Multiple packages, Multiple vulnerabilities fixed in 2011	Nessus	Gentoo Local Security Checks	critical
54899	Slackware 13.1 / current : shadow (SSA:2011-086-03)	Nessus	Slackware Local Security Checks	medium
52027	Debian DSA-2164-1 : shadow - insufficient input sanitization	Nessus	Debian Local Security Checks	medium
51997	Ubuntu 9.10 / 10.04 LTS / 10.10 : shadow vulnerability (USN-1065-1)	Nessus	Ubuntu Local Security Checks	medium

Detections

Analytics

CVE-2011-0721

high

Tenable Plugins

critical

medium

medium

medium