CVE-2021-43533 json
When parsing internationalized domain names, high bits of the characters in the URLs were sometimes stripped, resulting in inconsistencies…
published 2021-12-08 4 y ago modified 2026-06-17 4 mo ago also EUVD-2021-30462
- cvss
- 4.3
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.6%
- EPSS 0.6% chance of exploitation in 30 days, percentile 46%
- public exploits
- 0
- none known
Summary
When parsing internationalized domain names, high bits of the characters in the URLs were sometimes stripped, resulting in inconsistencies that could lead to user confusion or attacks such as phishing. This vulnerability affects Firefox < 94.
Patch / fix
- Mozilla Firefox 94
Exploit prediction
0.56% chance of exploitation in the next 30 days, higher than 46% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 4.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N |
| NVD | 2.0 | 4.3 | AV:N/AC:M/Au:N/C:N/I:P/A:N |
Affected products
- Mozilla Firefox
References
-
mozilla.org
/security/advisories/mfsa2021-48/
vendor-advisory
-
bugzilla.mozilla.org
/show_bug.cgi?id=1724233
issue-tracking, permissions-required, vendor-advisory
Sources
- CVE List CVE-2021-43533
- NVD CVE-2021-43533
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