How severe is CVE-2023-41991?

CVE-2023-41991 has a CVSS 3.1 base score of 5.5 (MEDIUM). EPSS estimates a 13.4% probability of exploitation in the next 30 days. It is listed in the CISA Known Exploited Vulnerabilities catalog.

CVE-2023-41991: Apple Multiple Products Improper Certificate

CISA Known Exploited Vulnerabilities

Apple Multiple Products Improper Certificate Validation Vulnerability is confirmed as actively exploited and is listed in the CISA KEV catalog.

Added to KEV

2023-09-25

Remediation due

2023-10-16

Required action
Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

CISA notes
https://support.apple.com/en-us/HT213926, https://support.apple.com/en-us/HT213927, https://support.apple.com/en-us/HT213928, https://support.apple.com/en-us/HT213929, https://support.apple.com/en-us/HT213931 ; https://nvd.nist.gov/vuln/detail/CVE-2023-41991

Description

A certificate validation issue was addressed. This issue is fixed in macOS Ventura 13.6, iOS 16.7 and iPadOS 16.7. A malicious app may be able to bypass signature validation. Apple is aware of a report that this issue may have been actively exploited against versions of iOS before iOS 16.7.

Severity

CVSS 3.1 · CISA5.5 MEDIUM

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N

SSVC · CISA-ADP

Exploitationactive

Automatableno

Technical impactpartial

Exploitation Context

as of October 14, 2026

All KEV statistics→

CISA added CVE-2023-41991 to the KEV catalog 4 days after its CVE record was published. The median for entries added in 2023 is 12 days.
It is one of 95 Apple entries in the CISA KEV catalog, and one of 21 added in 2023.
Its current EPSS score (13.4%) is higher than that of 29% of CISA KEV entries.

Affected Products

Vendor	Product	Affected versions
Apple	Apple iOS and iPadOS	unspecified to <16.7
Apple	Apple macOS	unspecified to <13.6

References

4 Links

Other references

Record Details

Published

2023-09-21

Last updated

2025-11-04

Assigner (CNA)

apple

Credited to

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CVE record data © The MITRE Corporation, used under the CVE Terms of Use. Exploited-in-the-wild data from the CISA Known Exploited Vulnerabilities catalog (CC0). Exploit prediction scores by FIRST EPSS (first.org/epss). This site is not endorsed or certified by MITRE, NVD, CISA, or FIRST.