Mozilla Firefox up to 108 URL incorrect regex

CVSS Meta Temp Score
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CTI Interest Score
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6.0$5k-$25k0.00

Summaryinfo

A vulnerability was found in Mozilla Firefox up to 108 and classified as problematic. This issue affects some unknown processing of the component URL Handler. Executing a manipulation can lead to incorrect regex. This vulnerability is tracked as CVE-2023-23603. The attack can be launched remotely. No exploit exists. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability has been found in Mozilla Firefox up to 108 (Web Browser) and classified as problematic. This vulnerability affects an unknown code of the component URL Handler. The manipulation with an unknown input leads to a incorrect regex vulnerability. The CWE definition for the vulnerability is CWE-185. The product specifies a regular expression in a way that causes data to be improperly matched or compared. As an impact it is known to affect confidentiality. CVE summarizes:

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.

The weakness was disclosed 01/17/2023 by Dan Veditz as Bug 1800832 as confirmed advisory (Website). The advisory is shared for download at bugzilla.mozilla.org. The advisory contains:

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 was named CVE-2023-23603. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $5k-$25k (estimation calculated on 12/18/2025).

Upgrading to version 109 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-2023-27703). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.1
VulDB Meta Temp Score: 6.0

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 6.5
NVD Vector: 🔍

CNA Base Score: 6.5
CNA Vector: 🔍

CVSSv2info

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

Exploitinginfo

Class: Incorrect regex
CWE: CWE-185 / CWE-697
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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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

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

Upgrade: Firefox 109

Timelineinfo

01/16/2023 🔍
01/17/2023 +1 days 🔍
01/17/2023 +0 days 🔍
01/19/2023 +2 days 🔍
12/18/2025 +1064 days 🔍

Sourcesinfo

Vendor: mozilla.org
Product: mozilla.org

Advisory: Bug 1800832
Researcher: Dan Veditz
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2023-23603 (🔍)
GCVE (CVE): GCVE-0-2023-23603
GCVE (VulDB): GCVE-100-218992
EUVD: 🔍

Entryinfo

Created: 01/19/2023 14:21
Updated: 12/18/2025 20:58
Changes: 01/19/2023 14:21 (18), 01/19/2023 14:25 (28), 02/15/2023 13:14 (1), 01/10/2025 21:38 (36), 10/14/2025 05:21 (1), 12/18/2025 20:58 (1)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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