---
id: CVE-2025-3030
title: >-
  Memory safety bugs present in Firefox 136, Thunderbird 136, Firefox ESR 128.8,
  and Thunderbird 128.8
summary: >-
  Memory safety bugs present in Firefox 136, Thunderbird 136, Firefox ESR 128.8,
  and Thunderbird 128.8. Some of these bugs showed evidence of memory corruption
  and we presume that with enough effort some of these could have been exploited
  …
severity: high
cvss: 8.1
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H'
cwe:
  - CWE-416
vendor: mozilla
product: firefox
affected:
  - firefox < 128.8.0
  - firefox < 136.0
  - thunderbird < 128.8.0
  - 'thunderbird >= 129.0, < 136.0'
patched:
  - firefox 136.0
  - thunderbird 136.0
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-2025-3030'
references:
  - url: >-
      https://bugzilla.mozilla.org/buglist.cgi?bug_id=1850615%2C1932468%2C1942551%2C1951017%2C1951494
    label: security@mozilla.org
  - url: 'https://www.mozilla.org/security/advisories/mfsa2025-20/'
    label: security@mozilla.org
  - url: 'https://www.mozilla.org/security/advisories/mfsa2025-22/'
    label: security@mozilla.org
  - url: 'https://www.mozilla.org/security/advisories/mfsa2025-23/'
    label: security@mozilla.org
  - url: 'https://www.mozilla.org/security/advisories/mfsa2025-24/'
    label: security@mozilla.org
  - url: 'https://lists.debian.org/debian-lts-announce/2025/04/msg00005.html'
    label: af854a3a-2127-422b-91ae-364da2661108
tags:
  - nvd
epss: 0.00495
epssPercentile: 0.40131
ingestedAt: '2026-09-30T18:17:24.431Z'
---

## Overview

Memory safety bugs present in Firefox 136, Thunderbird 136, Firefox ESR 128.8, and Thunderbird 128.8. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 137, Firefox ESR 128.9, Thunderbird 137, and Thunderbird 128.9.

## Affected

- `firefox < 128.8.0`
- `firefox < 136.0`
- `thunderbird < 128.8.0`
- `thunderbird >= 129.0, < 136.0`

## Remediation

Upgrade past the affected range:

- `firefox 136.0`
- `thunderbird 136.0`