CVE-2023-23603: Calls to console.log allowed bypassing Content Security Policy via format directive

Published Jan 17, 2023
·
Updated

Regular expressions used to filter out forbidden properties and values from style directives in calls to console.log weren't accounting for external URLs. Data could then be potentially exfiltrated from the browser. This vulnerability affects Firefox < 109, Firefox ESR < 102.7, and Thunderbird < 102.7.

Other sources

Regular expressions used to filter out forbidden properties and values from style directives in calls to <code>console.log</code> weren't accounting for external URLs. Data could then be potentially exfiltrated from the browser. This vulnerability affects Firefox < 109, Thunderbird < 102.7, and Firefox ESR < 102.7.

Regular expressions used to filter out forbidden properties and values from style directives in calls to console.log weren't accounting for external URLs. Data could then be potentially exfiltrated from the browser.

Mozilla

Affected Software

9 affected componentsFixes available
debian/firefox
118.0.2-1
debian/firefox-esr<=91.12.0esr-1~deb10u1
115.3.1esr-1~deb10u1102.15.0esr-1~deb11u1115.3.1esr-1~deb11u1102.15.1esr-1~deb12u1115.3.0esr-1~deb12u1115.3.0esr-1
debian/thunderbird<=1:91.12.0-1~deb10u1
1:115.3.1-1~deb10u11:102.13.1-1~deb11u11:115.3.1-1~deb11u11:102.15.1-1~deb12u11:115.3.1-1~deb12u11:115.3.1-1
Mozilla Thunderbird<102.7
102.7
Mozilla Firefox<109.0
Mozilla Firefox ESR<102.7
Mozilla Thunderbird<102.7
Mozilla Firefox ESR<102.7
102.7
Mozilla Firefox<109
109

Event History

Jan 17, 2023
CVE Published
12:00 AM
Jun 2, 2023
CVE Published
via MITRE·12:00 AM
Data Sourced
via MITRE·12:00 AM
Description
Data Sourced
05:15 PM
Description
Data Sourced
via NVD·05:15 PM
DescriptionSeverityWeaknessAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the vulnerability ID?

The vulnerability ID is CVE-2023-23603.

2

What is the severity of CVE-2023-23603?

The severity of CVE-2023-23603 is medium.

3

Which software versions are affected by CVE-2023-23603?

Firefox versions < 109, Thunderbird versions < 102.7, and Firefox ESR versions < 102.7 are affected.

4

How does CVE-2023-23603 affect the browser?

CVE-2023-23603 allows potential exfiltration of data from the browser.

5

Where can I find more information about CVE-2023-23603?

You can find more information about CVE-2023-23603 in the Mozilla Security Advisories: [mfsa2023-01](https://www.mozilla.org/security/advisories/mfsa2023-01/), [mfsa2023-03](https://www.mozilla.org/security/advisories/mfsa2023-03/), [mfsa2023-02](https://www.mozilla.org/security/advisories/mfsa2023-02/).

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