Mozilla Firefox up to 99 CSS information disclosure

CVSS Meta Temp Score
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CTI Interest Score
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5.3$0-$5k0.00

Summaryinfo

A vulnerability has been found in Mozilla Firefox up to 99 and classified as problematic. This impacts an unknown function of the component CSS Handler. The manipulation leads to information disclosure. This vulnerability is listed as CVE-2022-29916. The attack may be initiated remotely. There is no available exploit. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in Mozilla Firefox up to 99 (Web Browser). It has been rated as problematic. This issue affects an unknown part of the component CSS Handler. The manipulation with an unknown input leads to a information disclosure vulnerability. Using CWE to declare the problem leads to CWE-200. The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information. Impacted is confidentiality. The summary by CVE is:

Firefox behaved slightly differently for already known resources when loading CSS resources involving CSS variables. This could have been used to probe the browser history. This vulnerability affects Thunderbird < 91.9, Firefox ESR < 91.9, and Firefox < 100.

The weakness was presented 05/03/2022 by Mateusz Sionkowski as Bug 1760674 as confirmed advisory (Website). The advisory is shared at bugzilla.mozilla.org. The advisory contains:

Firefox behaved slightly differently for already known resources when loading CSS resources involving CSS variables. This could have been used to probe the browser history.
The identification of this vulnerability is CVE-2022-29916. It demands that the victim is doing some kind of user interaction. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1592 for this issue.

The vulnerability scanner Nessus provides a plugin with the ID 294768 (MiracleLinux 8 : firefox-91.9.0-1.el8.ML.1 (AXSA:2022-3174:10)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 100 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 Tenable (294768). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.4
VulDB Meta Temp Score: 5.3

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 6.5
NVD Vector: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Information disclosure
CWE: CWE-200 / CWE-284 / CWE-266
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 294768
Nessus Name: MiracleLinux 8 : firefox-91.9.0-1.el8.ML.1 (AXSA:2022-3174:10)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

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

Upgrade: Firefox 100

Timelineinfo

04/29/2022 🔍
05/03/2022 +4 days 🔍
05/03/2022 +0 days 🔍
09/30/2022 +150 days 🔍
01/21/2026 +1209 days 🔍

Sourcesinfo

Vendor: mozilla.org
Product: mozilla.org

Advisory: Bug 1760674
Researcher: Mateusz Sionkowski
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2022-29916 (🔍)
GCVE (CVE): GCVE-0-2022-29916
GCVE (VulDB): GCVE-100-209933

Entryinfo

Created: 09/30/2022 09:48
Updated: 01/21/2026 13:53
Changes: 09/30/2022 09:48 (17), 09/30/2022 09:52 (29), 10/26/2022 12:59 (1), 04/15/2025 18:01 (27), 01/21/2026 13:53 (2)
Complete: 🔍
Cache ID: 216::103

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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