CVE-2025-1942 - CVE House
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Status published Unknown CVE-2025-1942

Disclosure of uninitialized memory when .toUpperCase() causes string to get longer

Vulnerability Description

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.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

The following person or organization is credited with identifying this vulnerability, as recorded in the NVD database:

  • anbu

References

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Affected Vendor

Affected Software

Firefox, Thunderbird
Vulnerable Versions:
136

Timeline

Official Publish: March 4th, 2025
Last Modified: June 4th, 2026
Added to House: July 22nd, 2026

CVSS Vectors

No vector data available

Weaknesses (CWE)

No CWE data available

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.