CVE-2021-1855 json
A logic issue was addressed with improved state management.
published 5y ago modified 4mo ago also EUVD-2021-7319
- cvss
- 6.5
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.8%
- EPSS 0.8% chance of exploitation in 30 days, percentile 56%
- public exploits
- 0
- none known
Summary
A logic issue was addressed with improved state management. This issue is fixed in macOS Big Sur 11.3. A malicious website may be able to force unnecessary network connections to fetch its favicon.
Patch / fix
- Apple macOS 11.3
Is CVE-2021-1855 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerExploit prediction
0.79% chance of exploitation in the next 30 days, higher than 56% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N |
| NVD | 2.0 | 6.4 | AV:N/AC:L/Au:N/C:P/I:P/A:N |
Affected products
- Apple macOS
References
-
support.apple.com
/en-us/HT212325
vendor-advisory
Sources
- CVE List CVE-2021-1855
- NVD CVE-2021-1855
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