Mozilla Firefox up to 135 String.toUpperCase uninitialized pointer

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.9$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as problematic, was found in Mozilla Firefox up to 135. This impacts the function String.toUpperCase. Such manipulation leads to uninitialized pointer. This vulnerability is listed as CVE-2025-1942. The attack may be performed from remote. There is no available exploit. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in Mozilla Firefox up to 135. It has been rated as problematic. Affected by this issue is the function String.toUpperCase. The manipulation with an unknown input leads to a uninitialized pointer vulnerability. Using CWE to declare the problem leads to CWE-824. The product accesses or uses a pointer that has not been initialized. Impacted is confidentiality. CVE summarizes:

When String.toUpperCase() caused a string to get longer it was possible for uninitialized memory to be incorporated into the result string. This vulnerability was fixed in Firefox 136 and Thunderbird 136.

The advisory is available at bugzilla.mozilla.org. This vulnerability is handled as CVE-2025-1942 since 03/04/2025. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. Successful exploitation requires user interaction by the victim. Technical details are known, but there is no available exploit. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 04/15/2026).

The vulnerability scanner Nessus provides a plugin with the ID 232218 (Ubuntu 20.04 LTS : Firefox vulnerabilities (USN-7334-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 136 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (232218). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.1
VulDB Meta Temp Score: 6.9

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

ADP CISA Base Score: 9.8
ADP CISA Vector: 🔍

CVSSv2info

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

Exploitinginfo

Class: Uninitialized pointer
CWE: CWE-824 / CWE-908
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: 232218
Nessus Name: Ubuntu 20.04 LTS : Firefox vulnerabilities (USN-7334-1)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Firefox 136

Timelineinfo

03/04/2025 🔍
03/04/2025 +0 days 🔍
03/04/2025 +0 days 🔍
04/15/2026 +407 days 🔍

Sourcesinfo

Vendor: mozilla.org
Product: mozilla.org

Advisory: bugzilla.mozilla.org
Status: Confirmed

CVE: CVE-2025-1942 (🔍)
GCVE (CVE): GCVE-0-2025-1942
GCVE (VulDB): GCVE-100-298538

Entryinfo

Created: 03/04/2025 15:11
Updated: 04/15/2026 12:11
Changes: 03/04/2025 15:11 (55), 03/07/2025 05:49 (2), 04/15/2026 12:11 (13)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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