---
id: CVE-2025-3031
title: >-
  An attacker could read 32 bits of values spilled onto the stack in a JIT
  compiled function
summary: >-
  An attacker could read 32 bits of values spilled onto the stack in a JIT
  compiled function. This vulnerability was fixed in Firefox 137 and Thunderbird
  137.
severity: medium
cvss: 6.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N'
cwe:
  - CWE-200
vendor: mozilla
product: firefox
affected:
  - firefox < 137.0
  - thunderbird < 137.0
patched:
  - firefox 137.0
  - thunderbird 137.0
published: '2025-04-01'
updated: '2026-09-30'
sourceUpdated: '2026-09-30T18:10:00.190'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2025-3031'
references:
  - url: 'https://bugzilla.mozilla.org/show_bug.cgi?id=1947141'
    label: security@mozilla.org
  - url: 'https://www.mozilla.org/security/advisories/mfsa2025-20/'
    label: security@mozilla.org
  - url: 'https://www.mozilla.org/security/advisories/mfsa2025-23/'
    label: security@mozilla.org
tags:
  - nvd
epss: 0.00291
epssPercentile: 0.19594
ingestedAt: '2026-09-30T18:17:24.431Z'
---

## Overview

An attacker could read 32 bits of values spilled onto the stack in a JIT compiled function. This vulnerability was fixed in Firefox 137 and Thunderbird 137.

## Affected

- `firefox < 137.0`
- `thunderbird < 137.0`

## Remediation

Upgrade past the affected range:

- `firefox 137.0`
- `thunderbird 137.0`