The getImageData function in the ImageBufferCairo class in WebCore/platform/graphics/cairo/ImageBufferCairo.cpp in WebKit, as used in WebKitGTK+ prior to version 2.20.3 and WPE WebKit prior to version 2.20.1, is vulnerable to a heap-based buffer overflow triggered by an integer overflow, which could be abused by crafted HTML content.
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.
| Link | Tags |
|---|---|
| https://bugs.webkit.org/show_bug.cgi?id=186384 | permissions required vendor advisory |
| https://security.gentoo.org/glsa/201808-04 | vendor advisory |
| http://www.securityfocus.com/archive/1/542087/100/0/threaded | mailing list |
| https://www.exploit-db.com/exploits/45205/ | exploit |
| https://trac.webkit.org/changeset/232618 | third party advisory patch vendor advisory |
| https://usn.ubuntu.com/3687-1/ | third party advisory vendor advisory |
| http://packetstormsecurity.com/files/148200/WebKitGTK-Data-Leak-Code-Execution.html | vdb entry third party advisory |
| http://www.openwall.com/lists/oss-security/2018/06/14/1 | mailing list technical description |