CVE-2023-42916: in the CISA KEV catalogue

Apple Multiple Products WebKit Out-of-Bounds Read Vulnerability. CISA added CVE-2023-42916 to the Known Exploited Vulnerabilities catalogue on 2023-12-04 with a default due date of 2023-12-25. Known ransomware campaign use: Unknown. Forensic triage flag: No.

Apple iOS, iPadOS, macOS, and Safari WebKit contain an out-of-bounds read vulnerability that may disclose sensitive information when processing maliciously crafted web content. 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. (CISA description)

Vendor / product: Apple Multiple Products
CWE: CWE-125
CISA required action: Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.
EPSS: 18%, percentile 97 (scored 2026-11-03)

EPSS puts about 18 in 100 odds (18%) on exploitation activity being observed in the next 30 days. Its score is higher than or equal to that of 97% of scored CVEs. This is a model estimate about exploitation anywhere, not about your environment.

Vendor and reference links (from CISA)

Your own deadline under CISA BOD 26-04 depends on exposure, automatability and technical impact: work it out with the BOD 26-04 calculator.

Data dates. CISA KEV catalogue version 2026.11.03, released 2026-11-03, 1,767 entries (checked 2026-11-03). EPSS model v2026.06.15, scored 2026-11-03, 399,388 CVEs. Sources: CISA and FIRST (EPSS by FIRST; scores generated by Empirical Security). Copied to our own database and refreshed automatically; if a refresh fails, the previous copy keeps serving with its own date.

Frequently asked questions

Is CVE-2023-42916 in the CISA KEV catalogue?

Yes. CISA added CVE-2023-42916 (Apple Multiple Products WebKit Out-of-Bounds Read Vulnerability) to the Known Exploited Vulnerabilities catalogue on 2023-12-04. CISA's default due date for it is 2023-12-25.

Is CVE-2023-42916 used in ransomware attacks?

CISA marks known ransomware campaign use as Unknown for CVE-2023-42916. That means CISA lacks confirmation, not that ransomware groups do not use it.

What should I do about CVE-2023-42916?

CISA's required action: Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.

Sources

CISA, Known Exploited Vulnerabilities Catalog (accessed 2026-11-03)
FIRST, Exploit Prediction Scoring System (EPSS) (EPSS by FIRST; scores generated by Empirical Security)
NVD record for CVE-2023-42916