CVE-2026-28858
Remote buffer overflow in iOS/iPadOS kernel; may crash device.
Is CVE-2026-28858 being exploited?
Not confirmed. CVE-2026-28858 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.53% probability of exploitation in the next 30 days.
How severe is CVE-2026-28858?
CVE-2026-28858 is rated Critical with a CVSS score of 9.8. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-28858?
Yes. A fix has been recorded for CVE-2026-28858. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-28858 affect?
CVE-2026-28858 affects iOS 26.4, iPadOS 26.4. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-28858?
Update to iOS 26.4 / iPadOS 26.4 immediately
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Remote crash or kernel memory corruption; potential device instability and exploitation risk.
Patch when possible
- affected< 26.4
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.