Vulnerability Details CVE-2017-17821
WTF/wtf/FastBitVector.h in WebKit, as distributed in Safari Technology Preview Release 46, allows remote attackers to cause a denial of service (buffer overflow) or possibly have unspecified other impact because it calls the FastBitVectorWordOwner::resizeSlow function (in WTF/wtf/FastBitVector.cpp) for a purpose other than initializing a bitvector size, and resizeSlow mishandles cases where the old array length is greater than the new array length.
Exploit prediction scoring system (EPSS) score
EPSS Score 0.007
EPSS Ranking 70.6%
CVSS Severity
CVSS v3 Score 9.8
CVSS v2 Score 7.5
References
- https://bugs.webkit.org/show_bug.cgi?id=181020
- https://github.com/dwfault/PoCs/blob/master/WebKit%20Misuse%20of%20WTF:wtf:FastBitVector%20result%20in%20potential%20BOF/WebKit%20Misuse%20of%20WTF:wtf:FastBitVector%20result%20in%20potential%20BOF.md
- https://bugs.webkit.org/show_bug.cgi?id=181020
- https://github.com/dwfault/PoCs/blob/master/WebKit%20Misuse%20of%20WTF:wtf:FastBitVector%20result%20in%20potential%20BOF/WebKit%20Misuse%20of%20WTF:wtf:FastBitVector%20result%20in%20potential%20BOF.md