8.8

CVE-2021-1789: Apple Multiple Products Type Confusion Vulnerability

CVSS: 8.8v3.1HighKEVAnalyzed
AliasesUBUNTU-CVE-2021-1789DEBIAN-CVE-2021-1789
Published 02-04-2021Last modified 21-10-2025
Open JSON

Vulnerability summary

CVE-2021-1789 is a high (CVSS 8.8) Type Confusion vulnerability in Apple Multiple Products. It is known to be exploited: CISA lists it, first on 04-05-2022. EPSS estimates a 13.98% chance of exploitation in the next 30 days, higher than 96.5% of scored vulnerabilities.

Overall risk
85/100
0100
Critical · default modelHow is this calculated?
CVSS score
8.8/10
010
High · v3.1 (CVE.org)
EPSS score
13.98%
0%100%
Medium · -0.50 pp in 30 days
KEVListedCISA
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 10 · Related 6
DSA-4877-1MGASA-2021-0181OPENSUSE-SU-2021:0637-1OPENSUSE-SU-2024:11506-1RHSA-2021:4381RHSA-2025:10364

Timeline

  1. 02-04-2021
    PublishedVulnerability first disclosed.
  2. 04-05-2022
    Added to CISA KEVApple Multiple Products Type Confusion Vulnerability
  3. 25-05-2022
    CISA remediation dueApply updates per vendor instructions.
  4. 21-10-2025
    Last modifiedVulnerability information updated.

Description

A type confusion issue was addressed with improved state handling. This issue is fixed in macOS Big Sur 11.2, Security Update 2021-001 Catalina, Security Update 2021-001 Mojave, tvOS 14.4, watchOS 7.3, iOS 14.4 and iPadOS 14.4, Safari 14.0.3. Processing maliciously crafted web content may lead to arbitrary code execution.

CVSS metrics

5 scores · 4 sources · 2 versions

EPSS trend

Probability

13.98%

Chance of exploitation in the next 30 days

Percentile

97%

Versus all other CVEs

30-day change

-0.50 pp

From 14.48% on 19-09-2026

19-09-202619-10-2026
EPSS score
13.98%

Known exploited

Compare KEV catalogs
CISA KEVListed
Added
04-05-2022
Federal due date
25-05-2022

CISA required action

Apply updates per vendor instructions. nvd.nist.gov/vuln/detail/CVE-2021-1789

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Apple7 products
  • ios and ipados≥ unspecified, < 14.4
  • ipados< 14.4
  • iphone_os< 14.4
  • mac_os_x≥ 10.14, < 10.14.6 | ≥ 10.15, < 10.15.7 | 10.14.6 | 10.14.6:security_update_2019-004 | 10.14.6:security_update_2019-005 | 10.14.6:security_update_2019-006 | 10.14.6:security_update_2019-007 | 10.14.6:security_update_2020-001 | 10.14.6:security_update_2020-002 | 10.14.6:security_update_2020-003 | 10.14.6:security_update_2020-004 | 10.14.6:security_update_2020-005 | 10.14.6:security_update_2020-006 | 10.14.6:security_update_2020-007 | 10.14.6:supplemental_update | 10.14.6:supplemental_update_2 | 10.15.7 | 10.15.7:supplemental_update
  • macos≥ unspecified, < 11.2 | ≥ unspecified, < 7.3 | ≥ unspecified, < 14.4 | ≥ unspecified, < 14.0 | ≥ 11.0, < 11.2
Ubuntu5 products
  • qtwebkit-opensource-srcAll versions (No fix recorded)
  • qtwebkit-sourceAll versions (No fix recorded)
  • webkit2gtkAll versions (No fix recorded) | < 2.30.6-0ubuntu0.18.04.1 | < 2.30.6-0ubuntu0.20.04.1
  • webkitgtkAll versions (No fix recorded)
  • wpewebkitAll versions (No fix recorded)
Debian2 products
  • webkit2gtk< 2.30.6-1
  • wpewebkit< 2.30.6-1
Fedoraproject1 product
Webkitgtk1 product

5 vendors · 16 products

References

15 links
Show all 15 references