CVE-2025-1933 - CVE House
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Status published Unknown CVE-2025-1933

JIT corruption of WASM i32 return values on 64-bit CPUs

Vulnerability Description

On 64-bit CPUs, when the JIT compiles WASM i32 return values they can pick up bits from left over memory. This can potentially cause them to be treated as a different type. This vulnerability was fixed in Firefox 136, Firefox ESR 115.21, Firefox ESR 128.8, Thunderbird 136, and Thunderbird 128.8.

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:

  • Xiangwei Zhang and kkdong of Tencent Security YUNDING LAB

References

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Affected Vendor

Affected Software

Firefox, Thunderbird
Vulnerable Versions:
115.21, 128.8, 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.