MITRE description:

Buffer overflow in the X render (Xrender) extension in X.org X server 6.8.0 up to allows attackers to cause a denial of service (crash), as demonstrated by the (1) XRenderCompositeTriStrip and (2) XRenderCompositeTriFan requests in the rendertest from XCB xcb/xcb-demo, which leads to an incorrect memory allocation due to a typo in an expression that uses a "&" instead of a "*" operator. NOTE: the subject line of the original announcement used an incorrect CVE number for this issue.