Buffer overflow in Apple Safari
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.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.014 (71.1th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 71st percentile — 71.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.014 · newest: 0.014 · change: +0.000
Affected products
- Apple Safari — versions 46
Weakness classification (CWE)
References
- bugs.webkit.org/show_bug.cgi (Permissions Required)
- github.com/dwfault/PoCs/blob/master/WebKit Misuse of WTF:wtf:FastBitVector resu… (Third Party Advisory)
Frequently asked questions
- What is CVE-2017-17821?
- CVE-2017-17821 is a critical-severity vulnerability in Apple Safari, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 9.8/10. Published 2017-12-21.
- How severe is CVE-2017-17821?
- Critical severity. CVSS v3 base score is 9.8 out of 10.