CVE-2021-43533 json
When parsing internationalized domain names, high bits of the characters in the URLs were sometimes stripped, resulting in inconsistencies…
published 4y ago modified 4mo 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 47%
- 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
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Check with FencerExploit prediction
0.56% chance of exploitation in the next 30 days, higher than 47% of all scored CVEs (FIRST EPSS, 2026-11-09).
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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