CVE-2013-2179

Description

From CVE.org

X.Org xdm 1.1.10, 1.1.11, and possibly other versions, when performing authentication using certain implementations of the crypt API function that can return NULL, allows remote attackers to cause a denial of service (NULL pointer dereference and crash) by attempting to log into an account whose password field contains invalid characters, as demonstrated using the crypt function from glibc 2.17 and later with (1) the "!" character in the salt portion of a password field or (2) a password that has been encrypted using DES or MD5 in FIPS-140 mode.

Statement

Not Vulnerable. This issue does not affect the version of xorg-x11-xdm as shipped with Red Hat Enterprise Linux 5 and 6.

Common Vulnerability Scoring System (CVSS) Score Details

Info alert:Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).

The following CVSS metrics and score provided are preliminary and subject to review.

CVSS v2 Score Breakdown

Red HatNVDcve.org
Base Score1.94.3N/A
Attack VectorLocalNetworkN/A
Access ComplexityMediumMediumN/A
AuthenticationNoneNoneN/A
Confidentiality ImpactNoneNoneN/A
Integrity ImpactNoneNoneN/A
Availability ImpactPartialPartialN/A

Vector

Red Hat: AV:L/AC:M/Au:N/C:N/I:N/A:P

NVD: AV:N/AC:M/Au:N/C:N/I:N/A:P

Understanding the Weakness (CWE)

Availability

Technical Impact: DoS: Crash, Exit, or Restart

NULL pointer dereferences usually result in the failure of the process unless exception handling (on some platforms) is available and implemented. Even when exception handling is being used, it can still be very difficult to return the software to a safe state of operation.

Integrity,Confidentiality

Technical Impact: Execute Unauthorized Code or Commands; Read Memory; Modify Memory

In rare circumstances, when NULL is equivalent to the 0x0 memory address and privileged code can access it, then writing or reading memory is possible, which may lead to code execution.

Frequently Asked Questions

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