CVE-2021-1789
A type confusion issue was addressed with improved state handling. This issue is fixed in macOS Big Sur 11.2, Security Update 2021-001…
- Published
- Updated
- Reserved
- Assigned by
- apple
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.
Exploited in the wild
CISA lists this vulnerability in its Known Exploited Vulnerabilities catalog as Apple Multiple Products Type Confusion Vulnerability.
- Added
- 4 May 2022
- Fix due (US federal)
- 25 May 2022
- Used by ransomware
- Not known
Apply updates per vendor instructions.
Public exploit
An exploit or proof of concept is public: anyone can try it against an unpatched system. CISA's SSVC rates its exploitation: it is being exploited.
Timeline
ID reserved
By apple
- 4 months later
· 4 months later
Published
- 13 months later
· 13 months later
Added to CISA KEV
Known exploited in the wild
- 3 years later
· 3 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| CISA-ADPADP (enrichment) | 3.1 | High8.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H |
| NVDNVD · Analyzed | 3.1 | High8.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 14.0% · top 3.4% of all CVEs (7 Nov 2026)
- CISA SSVC
- Exploitation: active · Automatable: no · Technical impact: total
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.8.
Weakness
- Processing maliciously crafted web content may lead to arbitrary code execution
- CWE-843 Access of Resource Using Incompatible Type ('Type Confusion') (opens in a new tab)All about CWE-843 and its CVEs
Affected products
References (9)
- https://support.apple.com/en-us/HT212147 (opens in a new tab)x_refsource_MISCx_transferred
- https://support.apple.com/en-us/HT212146 (opens in a new tab)x_refsource_MISCx_transferred
- https://support.apple.com/en-us/HT212148 (opens in a new tab)x_refsource_MISCx_transferred
- https://support.apple.com/en-us/HT212149 (opens in a new tab)x_refsource_MISCx_transferred
- https://support.apple.com/en-us/HT212152 (opens in a new tab)x_refsource_MISCx_transferred
- FEDORA-2021-864dc37032 (opens in a new tab)vendor-advisoryx_refsource_FEDORAx_transferred
- FEDORA-2021-619711d709 (opens in a new tab)vendor-advisoryx_refsource_FEDORAx_transferred
- GLSA-202104-03 (opens in a new tab)vendor-advisoryx_refsource_GENTOOx_transferred
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-1789 (opens in a new tab)government-resource
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- CISA KEV catalog (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2021-1789)Record last updated .