What is CVE-2021-30763?

CVE-2021-30763 is a medium-severity vulnerability in Apple iOS, classified under Improper Input Validation. CVSS score: 5.5/10. Published 2021-09-08.

How severe is CVE-2021-30763?

Medium severity. CVSS v3 base score is 5.5 out of 10.

Is CVE-2021-30763 known to be exploited?

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

Improper input validation in Apple iOS

CVE-2021-30763

An input validation issue was addressed with improved input validation. This issue is fixed in iOS 14.7, watchOS 7.6. A shortcut may be able to bypass Internet permission requirements.

Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)

Published 2021-09-08 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N.

EPSS exploit prediction

EPSS: 0.008 (56.0th percentile), scored 2026-10-02.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 56th percentile — 56.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.008 · newest: 0.008 · change: 0.000

Affected products

Apple iOS — versions unspecified
Apple Ipados
Apple Iphone OS
Apple watchOS — versions unspecified

Weakness classification (CWE)

CWE-20 — Improper Input Validation

Public proof-of-concept exploits

0xilis/resume

References

support.apple.com/en-us/HT212601 (Vendor Advisory)
support.apple.com/en-us/HT212605 (Vendor Advisory)

Frequently asked questions

What is CVE-2021-30763?: CVE-2021-30763 is a medium-severity vulnerability in Apple iOS, classified under Improper Input Validation. CVSS score: 5.5/10. Published 2021-09-08.
How severe is CVE-2021-30763?: Medium severity. CVSS v3 base score is 5.5 out of 10.
Is CVE-2021-30763 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.