Exploited

CVE-2022-42856

Apple Safari / WebKit · Browsers and web engines

Apple iOS Type Confusion Vulnerability

At a glance

Exploited. Added to CISA’s catalog of exploited vulnerabilities on December 14, 2022.

Affected product: Apple Safari / WebKit (category Browsers and web engines, indicative classification). Name in CISA’s catalog: Apple iOS.

What should I do?

Apply the security update from Apple.

Deadline set by CISA for US federal agencies: 21 days (due January 4, 2023). It only binds those agencies, but it is a useful measure of urgency.

Apple security advisories page (general page, not the advisory for this vulnerability)
The vendor’s specific advisory is listed in the NVD references: CVE-2022-42856 on the NVD website.

Original text of the required action (CISA)

Apply updates per vendor instructions.

Timeline

December 14, 2022 Exploitation confirmed Added to CISA’s KEV catalog
December 15, 2022 Vulnerability published Publication date (NVD)
January 4, 2023 CISA deadline Remediation deadline set for US federal agencies

The facts, with their sources

Exploitation confirmed: Yes, on December 14, 2022 Date added to the catalog of exploited vulnerabilities. Exploitation itself may have started earlier. Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
Ransomware: No known use to date That does not guarantee it is not being used: the information is not public. Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
Hunt for compromise: Not requested by CISA Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
CISA required action: Apply the security update from Apple. Rewritten by this site from CISA’s original text. Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
CISA deadline: January 4, 2023, 21 days Set for US federal agencies: a measure of urgency, not an obligation elsewhere. Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
Vulnerability published: December 15, 2022 Source: National Vulnerability Database (NVD), collected September 29, 2026 at 15:00 UTC
Product according to CISA: Apple iOS Filed by this site under “Browsers and web engines” (indicative classification). Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H Technical detail of the score: attack vector, complexity, impact. Source: National Vulnerability Database (NVD), collected September 29, 2026 at 15:00 UTC

Severity and activity

8.8 / 10 CVSS severity: high

Score from the NVD. Collected Sep 29, 2026.

— Probability of exploitation in the next 30 days (EPSS)

FIRST’s EPSS model. Since exploitation is already confirmed, this figure is mostly useful to compare activity. Collected Sep 29, 2026.

Description

A type confusion issue was addressed with improved state handling. This issue is fixed in Safari 16.2, tvOS 16.2, macOS Ventura 13.1, iOS 15.7.2 and iPadOS 15.7.2, iOS 16.1.2. Processing maliciously crafted web content may lead to arbitrary code execution. Apple is aware of a report that this issue may have been actively exploited against versions of iOS released before iOS 15.1..

Apple iOS contains a type confusion vulnerability when processing maliciously crafted web content leading to code execution.

Summary from CISA (KEV catalog).

CERT-FR advisories

No advisory among the latest CERT-FR publications this site follows. That does not mean there are none.

Information reused under the Open Licence 2.0 (Etalab); the date of last update is shown for each advisory. This site is neither affiliated with nor endorsed by ANSSI.

Sources for this page

CISA KEV catalog: exploitation, date added, required action, deadline, ransomware.
NVD (NIST): CVSS severity, publication date, description, vendor references.
EPSS (FIRST): probability of exploitation.
CERT-FR: advisories and alerts (in French).
Brand and category: indicative classification by this site (method).