CVE-2016-4657: Apple iOS Webkit Memory Corruption Vulnerability
Actively exploited. At least one CVE in this advisory is listed in the CISA Known Exploited Vulnerabilities catalog — exploitation has been observed in the wild. Treat remediation as urgent.
Apple iOS WebKit contains a memory corruption vulnerability that allows attackers to execute remote code or cause a denial-of-service (DoS) via a crafted web site. This vulnerability could impact HTML parsers that use WebKit, including but not limited to Apple Safari and non-Apple products which rely on WebKit for HTML processing.
CSIRTS triage
- What
- A memory corruption vulnerability allows remote code execution or denial-of-service via a crafted website.
- Who is affected
- Users of Apple iOS and products relying on WebKit.
- Urgency
- Remediation is critical due to active exploitation and severity.
- Action
- Update iOS and WebKit-based applications.
AI-assisted analysis generated from the source advisory — verify against the original.
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Details
Original advisory: https://nvd.nist.gov/vuln/detail/CVE-2016-4657
Exploitation outlook
EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.
- Exploitation confirmedCVE-2016-4657Already exploited in the wild (CISA KEV) — the prediction phase is over. Patch now. Riskier than 99% of all scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2016-4657 | coverage & exploitation status | NVD · CVE.org |
Recent advisories for Apple iOS Webkit
A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.
- criticalexploitedCVE-2022-22620: Apple iOS, iPadOS, and macOS Webkit Use-After-Free Vulnerabilitycisa-kev · 2022-02-11
- criticalexploitedCVE-2021-1879: Apple iOS, iPadOS, and watchOS WebKit Cross-Site Scripting (XSS) Vulnerabilitycisa-kev · 2021-11-03
- criticalexploitedCVE-2021-30666: Apple iOS WebKit Buffer Overflow Vulnerabilitycisa-kev · 2021-11-03
- criticalexploitedCVE-2021-1870: Apple iOS, iPadOS, and macOS WebKit Remote Code Execution Vulnerabilitycisa-kev · 2021-11-03
- criticalexploitedCVE-2021-1871: Apple iOS, iPadOS, and macOS WebKit Remote Code Execution Vulnerabilitycisa-kev · 2021-11-03
- criticalexploitedCVE-2021-30762: Apple iOS WebKit Use-After-Free Vulnerabilitycisa-kev · 2021-11-03
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