CVE-2017-17821 json
WTF/wtf/FastBitVector.h in WebKit, as distributed in Safari Technology Preview Release 46, allows remote attackers to cause a denial of ser…
published 2017-12-21 8 y ago modified 2026-06-17 4 mo ago also EUVD-2017-8972
- cvss
- 9.8
- version 3.0, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.4%
- EPSS 1.4% chance of exploitation in 30 days, percentile 72%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- webkit2gtk Debian 14, Debian 13, Debian 12 2.22.0-2
debian advisories DEBIAN-CVE-2017-17821
Exploit prediction
1.38% chance of exploitation in the next 30 days, higher than 72% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.0 | 9.8 | CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVD | 2.0 | 7.5 | AV:N/AC:L/Au:N/C:P/I:P/A:P |
Classification
- Weakness
-
- CWE-119 Improper Restriction of Operations within the Bounds of a Memory Buffer
References
-
bugs.webkit.org
/show_bug.cgi?id=181020
permissions-required
-
github.com
/dwfault/PoCs/blob/master/WebKit%20Misuse%20of%20WTF:wtf:FastBitVector%20result%20in%20potential%20BOF/WebKit%
third-party-advisory
Sources
- CVE List CVE-2017-17821
- NVD CVE-2017-17821
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.