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The Mozilla Scalable Vector Graphics (SVG) viewer contains a heap buffer overflow vulnerability resulting from an unsigned integer wrap during the multiplication of the {{signed int}} value {{pen->num_vertices}} and the {{size_t}} value {{sizeof(cairo_pen_vertex_t)}} \[[VU#551436|AA. C References#VU551436]\].  The {{signed int}} operand is converted to {{size_t}} prior to the multiplication operation (see [INT02-C. Understand integer conversion rules|INT02-C. Understand integer conversion rules]), so that the multiplication takes place between two {{size_t}} integers, which are unsigned.

A Linux kernel vmsplice [exploit|BB. Definitions#exploit], described at \[[Wojtczuk 08|AA. C References#Wojtczuk 08]\], documents a vulnerability and exploit arising from a buffer overflow (caused by unsigned integer wrapping).

\[[Dowd 06|AA. C References#Dowd 06]\] Chapter 6, "C Language Issues" (Arithmetic Boundary Conditions, pp. 211-223)
\[[ISO/IEC 9899:1999|AA. C References#ISO/IEC 9899-1999]\] Section 6.2.5, "Types," Section 6.5, "Expressions," and Section 7.10, "Sizes of integer types {{<limits.h>}}"
\[[ISO/IEC PDTR 24772|AA. C References#ISO/IEC PDTR 24772]\] "XYY Wrap-around Error"
\[[MITRE 07|AA. C References#MITRE 07]\] [CWE ID 190|http://cwe.mitre.org/data/definitions/190.html], "Integer Overflow (Wrap or Wraparound)"
\[[Seacord 05|AA. C References#Seacord 05]\] Chapter 5, "Integers"
\[[Viega 05|AA. C References#Viega 05]\] Section 5.2.7, "Integer overflow"
\[[VU#551436|AA. C References#VU551436]\]
\[[Warren 02|AA. C References#Warren 02]\] Chapter 2, "Basics"
\[[Wojtczuk 08|AA. C References#Wojtczuk 08]\]
\[[xorl 2009|AA. C References#xorl 2009]\] ["CVE-2009-1385: Linux kernel E1000 Integer Underflow"|http://xorl.wordpress.com/2009/06/10/cve-2009-1385-linux-kernel-e1000-integer-underflow/]