SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2021-43532

This vulnerability affects Firefox < 94.

MEDIUM 6.1EPSS 0.53%

Does this matter?

Lower severity and a low EPSS score (0.53%). Track it; it rarely justifies an emergency change on its own.

Description

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.

CVSS 3.1
6.1 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
EPSS
0.53% probability · 43th percentile
CISA KEV
Not listed
Weakness
CWE-601
Affected
mozilla/firefox
Source
security@mozilla.org

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.