Mozilla Firefox up to 111 Debugging API use after free

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.9$5k-$25k0.00

Summaryinfo

A vulnerability identified as critical has been detected in Mozilla Firefox up to 111. This affects an unknown part of the component Debugging API. This manipulation causes use after free. This vulnerability is tracked as CVE-2023-29543. The attack is possible to be carried out remotely. No exploit exists. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in Mozilla Firefox up to 111 (Web Browser). It has been declared as critical. Affected by this vulnerability is some unknown functionality of the component Debugging API. The manipulation with an unknown input leads to a use after free vulnerability. The CWE definition for the vulnerability is CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

An attacker could have caused memory corruption and a potentially exploitable use-after-free of a pointer in a global object's debugger vector. This vulnerability affects Firefox for Android < 112, Firefox < 112, and Focus for Android < 112.

The weakness was disclosed 04/11/2023 by Lukas Bernhard as Bug 1816158 as confirmed advisory (Website). The advisory is shared at bugzilla.mozilla.org. The advisory contains:

An attacker could have caused memory corruption and a potentially exploitable use-after-free of a pointer in a global object's debugger vector.
This vulnerability is known as CVE-2023-29543. It demands that the victim is doing some kind of user interaction. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 12/10/2025).

Upgrading to version 112 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-2023-33085). 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: 8.0
VulDB Meta Temp Score: 7.9

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

NVD Base Score: 8.8
NVD Vector: 🔍

CNA Base Score: 8.8
CNA Vector: 🔍

CVSSv2info

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

Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
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 112

Timelineinfo

04/07/2023 🔍
04/11/2023 +4 days 🔍
04/11/2023 +0 days 🔍
04/14/2023 +3 days 🔍
12/10/2025 +971 days 🔍

Sourcesinfo

Vendor: mozilla.org
Product: mozilla.org

Advisory: Bug 1816158
Researcher: Lukas Bernhard
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2023-29543 (🔍)
GCVE (CVE): GCVE-0-2023-29543
GCVE (VulDB): GCVE-100-225997
EUVD: 🔍

Entryinfo

Created: 04/14/2023 16:35
Updated: 12/10/2025 18:11
Changes: 04/14/2023 16:35 (18), 04/14/2023 16:38 (28), 05/03/2023 12:21 (1), 01/10/2025 22:47 (36), 04/27/2025 09:49 (3), 12/10/2025 18:11 (1)
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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