CVE-2021-1879 kev in the critical feed json
This issue was addressed by improved management of object lifetimes.
published 2021-04-02 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-7343
- cvss
- 6.1
- version 3.1, CNA
- cisa kev
- Exploited
- added 2021-11-03
- epss
- 7.1%
- EPSS 7.1% chance of exploitation in 30 days, percentile 94%
- public exploits
- 0
- none known
Summary
This issue was addressed by improved management of object lifetimes. This issue is fixed in iOS 12.5.2, iOS 14.4.2 and iPadOS 14.4.2, watchOS 7.3.3. Processing maliciously crafted web content may lead to universal cross site scripting. Apple is aware of a report that this issue may have been actively exploited..
Patch / fix
cisa required action Apply updates per vendor instructions.
- Apple iOS and iPadOS 14.4
- Apple iOS 12.5
- Apple watchOS 7.3
Timeline
- 0-day patched (Project Zero)
- Published
- Added to CISA KEV
- CISA patch deadline
- CISA SSVC: exploitation active
Known exploited
- Added
- 5 y ago
- Patch by
- 2021-11-17 (4 y ago)
- Ransomware
- Not known
- Required action
- Apply updates per vendor instructions.
- Vendor, product
- Apple, iOS, iPadOS, and watchOS
- CISA name
- Apple iOS, iPadOS, and watchOS WebKit Cross-Site Scripting (XSS) Vulnerability
Zero-day
Detected in real attacks while still unknown to the vendor and the public, per Google Project Zero's 0day In-the-Wild tracker.
- Patched
- 2021-03-26
- Details
- project zero root cause analysis
CISA SSVC
- Exploitation
- Active, exploited in the wild
- Automatable
- no
- Technical impact
- partial
- Assessed
- 21 mo ago
Exploit prediction
7.08% chance of exploitation in the next 30 days, higher than 94% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CISA ADP | 3.1 | 6.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |
| NVD | 3.1 | 6.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |
| CNA | 3.1 | 6.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |
| NVD | 2.0 | 4.3 | AV:N/AC:M/Au:N/C:N/I:P/A:N |
Affected products
- Apple iOS and iPadOS
- Apple iOS
- Apple watchOS
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
References
-
support.apple.com
/en-us/HT212256
release-notes, vendor-advisory
-
support.apple.com
/en-us/HT212257
release-notes, vendor-advisory
-
support.apple.com
/en-us/HT212258
release-notes, vendor-advisory
-
cisa.gov
/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-1879
government-resource, us-government-resource
Sources
- CVE List CVE-2021-1879
- NVD CVE-2021-1879
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.