Integer overflow in libpng, as used in Google Chrome before 17.0.963.56, allows remote attackers to cause a denial of service or possibly have unspecified other impact via unknown vectors that trigger an integer truncation.
Integer Overflow or Wraparound The product performs a calculation that can
produce an integer overflow or wraparound when the logic
assumes that the resulting value will always be larger than
the original value. This occurs when an integer value is
incremented to a value that is too large to store in the
associated representation. When this occurs, the value may
become a very small or negative number.