CVE-2021-43532 json
The 'Copy Image Link' context menu action would copy the final image URL after redirects.
published 2021-12-08 4 y ago modified 2026-06-17 4 mo ago also EUVD-2021-30461
- cvss
- 6.1
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.5%
- EPSS 0.5% chance of exploitation in 30 days, percentile 46%
- public exploits
- 0
- none known
Summary
The 'Copy Image Link' context menu action would copy the final image URL after redirects. By embedding an image that triggered authentication flows - in conjunction with a Content Security Policy that stopped a redirection chain in the middle - the final image URL could be one that contained an authentication token used to takeover a user account. If a website tricked a user into copy and pasting the image link back to the page, the page would be able to steal the authentication tokens. This was fixed by making the action return the original URL, before any redirects. This vulnerability affects Firefox < 94.
Patch / fix
- Mozilla Firefox 94
Exploit prediction
0.55% 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 | 6.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |
| NVD | 2.0 | 5.8 | AV:N/AC:M/Au:N/C:P/I:P/A:N |
Affected products
- Mozilla Firefox
Classification
- Weakness
-
- CWE-601 URL Redirection to Untrusted Site
References
-
mozilla.org
/security/advisories/mfsa2021-48/
vendor-advisory
-
bugzilla.mozilla.org
/show_bug.cgi?id=1719203
issue-tracking, permissions-required, vendor-advisory
Sources
- CVE List CVE-2021-43532
- NVD CVE-2021-43532
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