CVE-2021-23969: As specified in the W3C Content Security Policy draft, when creating a violation report, "User agents need to ensure that the source file is the URL requested by the page,…

Description

As specified in the W3C Content Security Policy draft, when creating a violation report, "User agents need to ensure that the source file is the URL requested by the page, pre-redirects. If that’s not possible, user agents need to strip the URL down to an origin to avoid unintentional leakage." Under certain types of redirects, Firefox incorrectly set the source file to be the destination of the redirects. This was fixed to be the redirect destination's origin. This vulnerability affects Firefox < 86, Thunderbird < 78.8, and Firefox ESR < 78.8.

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N

Attack vector

Network

Complexity

Low

Privileges

None

User interaction

Required

Confidentiality

Low

Integrity

None

Availability

None

Scope

Unchanged

Exploitation

Is it being used?

Exploit prediction (EPSS)1.2% · higher than 68% of CVEs

Exploited in the wildNo evidence yet

CISA KEVNot listed

Ransomware campaign useNot known

Affected products

Which versions

FI

Firefox · Mozilla

before 86.0 · source: NVD

DL

Debian Linux · Debian

9.0; 10.0 · source: NVD

FE

Firefox Esr · Mozilla

before 78.8 · source: NVD

TH

Thunderbird · Mozilla

before 78.8 · source: NVD