Mozilla Firefox up to 109 ~ScriptLoadContext use after free

CVSS Meta Temp Score
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CTI Interest Score
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7.9$5k-$25k0.00

Summaryinfo

A vulnerability was found in Mozilla Firefox up to 109. It has been classified as critical. Affected is the function mozilla::dom::ScriptLoadContext::~ScriptLoadContext. This manipulation causes use after free. The identification of this vulnerability is CVE-2023-25739. It is possible to initiate the attack remotely. There is no exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in Mozilla Firefox up to 109 (Web Browser). It has been declared as critical. Affected by this vulnerability is the function mozilla::dom::ScriptLoadContext::~ScriptLoadContext. 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:

Module load requests that failed were not being checked as to whether or not they were cancelled causing a use-after-free in <code>ScriptLoadContext</code>. This vulnerability affects Firefox < 110, Thunderbird < 102.8, and Firefox ESR < 102.8.

The weakness was shared 02/14/2023 by Holger Fuhrmannek as Bug 1811939 as confirmed advisory (Website). It is possible to read the advisory at bugzilla.mozilla.org. The advisory contains:

Module load requests that failed were not being checked as to whether or not they were cancelled causing a use-after-free in ScriptLoadContext.
This vulnerability is known as CVE-2023-25739. It demands that the victim is doing some kind of user interaction. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 11/01/2025).

The vulnerability scanner Nessus provides a plugin with the ID 245197 (Linux Distros Unpatched Vulnerability : CVE-2023-25739), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 110 eliminates this vulnerability. A possible mitigation has been published immediately after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (245197) and EUVD (EUVD-2023-29646). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

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Version

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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

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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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Nessus ID: 245197
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2023-25739

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

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

Upgrade: Firefox 110

Timelineinfo

02/13/2023 🔍
02/14/2023 +1 days 🔍
02/14/2023 +0 days 🔍
03/02/2023 +16 days 🔍
11/01/2025 +975 days 🔍

Sourcesinfo

Vendor: mozilla.org
Product: mozilla.org

Advisory: Bug 1811939
Researcher: Holger Fuhrmannek
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2023-25739 (🔍)
GCVE (CVE): GCVE-0-2023-25739
GCVE (VulDB): GCVE-100-222199
EUVD: 🔍

Entryinfo

Created: 03/02/2023 15:10
Updated: 11/01/2025 23:38
Changes: 03/02/2023 15:10 (18), 03/02/2023 15:13 (28), 03/30/2023 16:02 (1), 01/09/2025 23:00 (36), 04/27/2025 20:47 (3), 08/07/2025 23:19 (2), 11/01/2025 23:38 (1)
Complete: 🔍
Cache ID: 216::103

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

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