What is CVE-2026-28858?

CVE-2026-28858 is a critical-severity vulnerability in Apple Ios And Ipados, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 9.8/10. Published 2026-03-25.

How severe is CVE-2026-28858?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Is CVE-2026-28858 known to be exploited?

1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Buffer overflow in Apple Ios And Ipados

CVE-2026-28858

A buffer overflow was addressed with improved bounds checking. This issue is fixed in iOS 26.4 and iPadOS 26.4. A remote user may be able to cause unexpected system termination or corrupt kernel memory.

Vulnerability class: Buffer Overflow

EPSS: 0.005 (41.6th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

CWE-120 — Buffer Copy without Checking Size of Input (Classic Buffer Overflow)

Public proof-of-concept exploits

kaleth4/CVE-2026-28858

References

product-security@apple.com (Vendor Advisory)

Frequently asked questions

What is CVE-2026-28858?: CVE-2026-28858 is a critical-severity vulnerability in Apple Ios And Ipados, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 9.8/10. Published 2026-03-25.
How severe is CVE-2026-28858?: Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2026-28858 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.