CVE-2013-4143

The (1) checkPasswd and (2) checkGroupXlockPasswds functions in xlockmore before 5.43 do not properly handle when a NULL value is returned upon an error by the crypt or dispcrypt function as implemented in glibc 2.17 and later, which allows attackers to bypass the screen lock via vectors related to invalid salts.

Published: 2014-05-30 Last update: 2026-05-06 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2013-4143 is rated Low Risk (14.1/100): CVSS Low severity, with low exploitation likelihood (EPSS 0.05%). Low composite risk—no urgent action required; patch on your normal maintenance cycle and revisit priority if CVSS or EPSS increases.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2013-4143

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2023-03-07 0.89% 0.05% -0.84%
2 2022-02-04 — 0.89% —

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2013-4143

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
2.1 2.0 LOW
AV:L/AC:L/Au:N/C:N/I:N/A:P Click to expand
Access vector (AV:L)
Requires local access to the target system.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:P)
Partial availability impact.
 3.9 2.9 [email protected]

Weakness enumeration for CVE-2013-4143

OS Trackers for CVE-2013-4143

vendor priority summary link
gentoo normal CVE-2013-4143: 1 GLSA(s) (201309-03), 1 atom(s) (x11-misc/xlockmore); latest impact normal. https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2013-4143

NVD evaluator notes for CVE-2013-4143

Comment: per http://cwe.mitre.org/data/definitions/476.html "CWE-476: NULL Pointer Dereference"

Affected software / configurations for CVE-2013-4143

Vendor Product Version Raw CPE
david_bagley xlockmore <= 5.42 cpe:2.3:a:david_bagley:xlockmore:*:*:*:*:*:*:*:*
david_bagley xlockmore 5.24 cpe:2.3:a:david_bagley:xlockmore:5.24:*:*:*:*:*:*:*
david_bagley xlockmore 5.25 cpe:2.3:a:david_bagley:xlockmore:5.25:*:*:*:*:*:*:*
david_bagley xlockmore 5.26 cpe:2.3:a:david_bagley:xlockmore:5.26:*:*:*:*:*:*:*
david_bagley xlockmore 5.27 cpe:2.3:a:david_bagley:xlockmore:5.27:*:*:*:*:*:*:*
david_bagley xlockmore 5.28 cpe:2.3:a:david_bagley:xlockmore:5.28:*:*:*:*:*:*:*
david_bagley xlockmore 5.29 cpe:2.3:a:david_bagley:xlockmore:5.29:*:*:*:*:*:*:*
david_bagley xlockmore 5.30 cpe:2.3:a:david_bagley:xlockmore:5.30:*:*:*:*:*:*:*
david_bagley xlockmore 5.31 cpe:2.3:a:david_bagley:xlockmore:5.31:*:*:*:*:*:*:*
david_bagley xlockmore 5.32 cpe:2.3:a:david_bagley:xlockmore:5.32:*:*:*:*:*:*:*
david_bagley xlockmore 5.33 cpe:2.3:a:david_bagley:xlockmore:5.33:*:*:*:*:*:*:*
david_bagley xlockmore 5.34 cpe:2.3:a:david_bagley:xlockmore:5.34:*:*:*:*:*:*:*
david_bagley xlockmore 5.35 cpe:2.3:a:david_bagley:xlockmore:5.35:*:*:*:*:*:*:*
david_bagley xlockmore 5.36 cpe:2.3:a:david_bagley:xlockmore:5.36:*:*:*:*:*:*:*
david_bagley xlockmore 5.37 cpe:2.3:a:david_bagley:xlockmore:5.37:*:*:*:*:*:*:*
david_bagley xlockmore 5.38 cpe:2.3:a:david_bagley:xlockmore:5.38:*:*:*:*:*:*:*
david_bagley xlockmore 5.39 cpe:2.3:a:david_bagley:xlockmore:5.39:*:*:*:*:*:*:*
david_bagley xlockmore 5.40 cpe:2.3:a:david_bagley:xlockmore:5.40:*:*:*:*:*:*:*
david_bagley xlockmore 5.41 cpe:2.3:a:david_bagley:xlockmore:5.41:*:*:*:*:*:*:*

References for CVE-2013-4143

cvelogic Threat Intelligence