32-bit stack disclosure via mismatched JIT slots
Published Apr 1, 2025 · Updated Apr 13, 2026
Information disclosure in Mozilla Firefox and Thunderbird before 137 allows remote attackers to read 32 bits from JIT stack spills. The JIT optimizer handles stack slots of different sizes incorrectly, allowing a compiled function to expose a spilled 32-bit value. Exploitation requires code to reach JIT compilation; the bounded consequence is disclosure of one 32-bit value from the process stack.
Summary
What happened
Information disclosure in Mozilla Firefox and Thunderbird before 137 allows remote attackers to read 32 bits from JIT stack spills. The JIT optimizer handles stack slots of different sizes incorrectly, allowing a compiled function to expose a spilled 32-bit value. Exploitation requires code to reach JIT compilation; the bounded consequence is disclosure of one 32-bit value from the process stack.
The record
- CVE
- CVE-2025-3031
- Published
- Apr 1, 2025
- Updated
- Apr 13, 2026
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-200
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Apr 1, 2025CVE publishedPublication date reported by the CVE source.
- Apr 13, 2026Record updatedLatest update available in the CVE record.
Exploitability
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What is affected?
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Published CVSS scores
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Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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