The png_check_keyword function in pngwutil.c in libpng before 1.0.42, and 1.2.x before 1.2.34, might allow context-dependent attackers to set the value of an arbitrary memory location to zero via vectors involving creation of crafted PNG files with keywords, related to an implicit cast of the '\0' character constant to a NULL pointer. NOTE: some sources incorrectly report this as a double free vulnerability.
CVSS Severity (version 2.0):
Impact Subscore: 2.9
Exploitability Subscore: 10.0
CVSS Version 2 Metrics:
Access Vector: Network exploitable
Access Complexity: Low
Authentication: Not required to exploit
Impact Type: Allows unauthorized modification
Official Statement from Red Hat (02/11/2009)
Red Hat does not consider this bug to be a security issue. For a more detailed explanation, please see the following bug:
References to Advisories, Solutions, and Tools
By selecting these links, you will be leaving NIST webspace. We have provided these links to other web sites because
they may have information that would be of interest to you. No inferences should be drawn on account of other sites
being referenced, or not, from this page. There may be other web sites that are more appropriate for your purpose.
NIST does not necessarily endorse the views expressed, or concur with the facts presented on these sites. Further,
NIST does not endorse any commercial products that may be mentioned on these sites. Please address comments about
this page to email@example.com.
[oss-security] 20090109 libpng non issue
[png-mng-implement] 20081126 Memory overwriting bug in png_check_keyword()