CVE-2022-40956

Mozilla: Content-Security-Policy base-uri bypass

Severity Score

6.1

*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

*SSVC

Descriptions

When injecting an HTML base element, some requests would ignore the CSP's base-uri settings and accept the injected element's base instead. This vulnerability affects Firefox ESR < 102.3, Thunderbird < 102.3, and Firefox < 105.

Al inyectar un elemento base HTML, algunas solicitudes ignorarían la configuración de uri base del CSP y aceptarían la base del elemento inyectado. Esta vulnerabilidad afecta a Firefox ESR < 102.3, Thunderbird < 102.3 y Firefox < 105.

A flaw was found in Mozilla. The Mozilla Foundation Security Advisory describes the issue that when injecting an HTML base element; some requests would ignore the CSP's base-uri settings and accept the injected element's base instead.

Mozilla Firefox is an open-source web browser, designed for standards compliance, performance, and portability. This update upgrades Firefox to version 102.3.0 ESR. Issues addressed include a bypass vulnerability.

*Credits: N/A

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Changed

Confidentiality

Low

Integrity

Low

Availability

None

Attack Vector

Network

Attack Complexity

Low

Authentication

None

Confidentiality

Partial

Integrity

Partial

Availability

None

* Common Vulnerability Scoring System

SSVC

Decision:-

Exploitation

Automatable

Tech. Impact

* Organization's Worst-case Scenario

Timeline

2022-09-19 CVE Reserved
2022-09-27 CVE Published
2024-08-03 CVE Updated
2025-03-30 EPSS Updated
---------- Exploited in Wild
---------- KEV Due Date
---------- First Exploit

CWE

CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CWE-1021: Improper Restriction of Rendered UI Layers or Frames

CAPEC

References (5)

URL	Tag	Source

URL	Date	SRC

URL	Date	SRC

URL	Date	SRC
https://www.mozilla.org/security/advisories/mfsa2022-40	2022-12-30
https://www.mozilla.org/security/advisories/mfsa2022-41	2022-12-30
https://www.mozilla.org/security/advisories/mfsa2022-42	2022-12-30
https://access.redhat.com/security/cve/CVE-2022-40956	2022-09-26
https://bugzilla.redhat.com/show_bug.cgi?id=2128795	2022-09-26

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Mozilla Search vendor "Mozilla"		Firefox Search vendor "Mozilla" for product "Firefox"				< 105.0 Search vendor "Mozilla" for product "Firefox" and version " < 105.0"		-		Affected
Mozilla Search vendor "Mozilla"		Firefox Esr Search vendor "Mozilla" for product "Firefox Esr"				< 102.3 Search vendor "Mozilla" for product "Firefox Esr" and version " < 102.3"		-		Affected
Mozilla Search vendor "Mozilla"		Thunderbird Search vendor "Mozilla" for product "Thunderbird"				< 102.3 Search vendor "Mozilla" for product "Thunderbird" and version " < 102.3"		-		Affected