Mozilla Firefox up to 95 Worker Remote Code Execution

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
6.0	$0-$5k	0.00

Summaryinfo

A vulnerability classified as critical has been found in Mozilla Firefox up to 95. The affected element is an unknown function of the component Worker Handler. The manipulation leads to an unknown weakness. This vulnerability is documented as CVE-2022-22763. The attack can be initiated remotely. There is not any exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in Mozilla Firefox up to 95 (Web Browser) and classified as critical. This issue affects some unknown processing of the component Worker Handler. Impacted is confidentiality, integrity, and availability.

The weakness was released 01/11/2022 by Mozilla Fuzzing Team as Bug 1740534 as confirmed advisory (Website). It is possible to read the advisory at bugzilla.mozilla.org. The advisory contains:

When a worker is shutdown, it was possible to cause script to run late in the lifecycle, at a point after where it should not be possible.

The identification of this vulnerability is CVE-2022-22763. It demands that the victim is doing some kind of user interaction. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 04/29/2026).

Upgrading to version 96 eliminates this vulnerability. A possible mitigation has been published immediately after the disclosure of the vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2022-27906). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

• Web Browser

Vendor

• Mozilla

Name

• Firefox

Version

• 95

License

• open-source

Website

• Vendor: https://www.mozilla.org/
• Product: https://www.mozilla.org/en-US/firefox/

CPE 2.3info

• 🔍

CPE 2.2info

• 🔍

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.0

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Remote Code Execution
CWE: Unknown
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍

Upgrade: Firefox 96

Timelineinfo

01/07/2022 🔍
01/11/2022 +4 days 🔍
01/11/2022 +0 days 🔍
09/29/2022 +261 days 🔍
04/29/2026 +1308 days 🔍

Sourcesinfo

Vendor: mozilla.org
Product: mozilla.org

Advisory: Bug 1740534
Researcher: Mozilla Fuzzing Team
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2022-22763 (🔍)
GCVE (CVE): GCVE-0-2022-22763
GCVE (VulDB): GCVE-100-209831
EUVD: 🔍

Entryinfo

Created: 09/29/2022 15:26
Updated: 04/29/2026 08:29
Changes: 09/29/2022 15:26 (17), 09/29/2022 15:29 (28), 10/25/2022 15:40 (1), 04/29/2026 08:29 (15)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

Discussion

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