CVE-2025-13025: Firefox Privilege Escalation Vulnerability

CVE-2025-13025 Overview

CVE-2025-13025 is a boundary condition vulnerability in the Graphics: WebGPU component of Mozilla Firefox and Thunderbird. Mozilla addressed the issue in Firefox 145 and Thunderbird 145. The flaw is reachable over the network through web content that exercises the WebGPU API, with no privileges or user interaction required beyond visiting a malicious page. According to the published CVSS vector, the primary impact is to integrity rather than confidentiality or availability. Mozilla tracks the issue under advisories MFSA-2025-87 and MFSA-2025-90, with internal triage in Mozilla Bug #1994022.

Critical Impact

A remote attacker can serve crafted WebGPU content to violate boundary conditions in the graphics pipeline, leading to integrity compromise within the browser process.

Affected Products

• Mozilla Firefox versions prior to 145
• Mozilla Thunderbird versions prior to 145
• Any downstream distributions packaging affected Firefox or Thunderbird builds

Discovery Timeline

• 2025-11-11 - CVE-2025-13025 published to NVD
• 2026-04-13 - Last updated in NVD database

Technical Details for CVE-2025-13025

Vulnerability Analysis

The vulnerability resides in the WebGPU implementation inside Firefox's Graphics subsystem. WebGPU exposes low-level GPU functionality to web content, including buffer allocation, command encoding, and shader execution. The component fails to correctly enforce boundary conditions when handling certain WebGPU operations. As a result, operations that should be rejected or clamped can proceed against memory or state outside their intended range. Mozilla classifies this issue under [CWE-276], and the CVSS vector indicates a high-integrity impact with no confidentiality or availability loss. The exploitation surface is the standard web content sandbox, so any site loaded in a vulnerable browser can attempt to trigger the condition.

Root Cause

The root cause is improper validation of bounds in WebGPU resource or command handling. When the component computes or checks limits, it accepts values that exceed the intended range. Subsequent operations then act on out-of-range indices, sizes, or descriptors. See Mozilla Bug #1994022 for the upstream technical record.

Attack Vector

An attacker hosts a page that issues crafted WebGPU calls. When a victim visits the page in an unpatched Firefox or Thunderbird build with WebGPU enabled, the calls trigger the boundary violation. No authentication or user interaction beyond page load is required. The result is integrity corruption of internal browser state usable as a primitive in chained exploits.

No public proof-of-concept code is associated with this CVE. Refer to Mozilla Security Advisory MFSA-2025-87 for vendor-provided technical context.

Detection Methods for CVE-2025-13025

Indicators of Compromise

• Firefox or Thunderbird processes with versions below 145 running in the environment, identifiable from process telemetry and software inventory.
• Browser crash reports referencing the wgpu, webgpu, or gfx modules following navigation to untrusted sites.
• Outbound connections from firefox.exe or thunderbird.exe to newly registered domains hosting WebGPU-heavy content.

Detection Strategies

• Inventory installed Firefox and Thunderbird builds across endpoints and flag versions earlier than 145 as vulnerable.
• Correlate browser crash dumps with navigation history to identify pages that exercise WebGPU and produce faults in the graphics stack.
• Hunt for child processes spawned by Firefox or Thunderbird immediately after WebGPU-related crashes, which can indicate exploitation chains.

Monitoring Recommendations

• Enable browser crash and telemetry forwarding to a centralized log store and alert on repeated faults in WebGPU modules.
• Monitor endpoint EDR telemetry for anomalous memory access patterns or sandbox escapes originating from browser content processes.
• Track outbound web traffic from user endpoints for connections to domains scoring high in threat-intelligence feeds while users are running outdated browser builds.

How to Mitigate CVE-2025-13025

Immediate Actions Required

• Upgrade Mozilla Firefox to version 145 or later on all endpoints, including managed and BYOD devices.
• Upgrade Mozilla Thunderbird to version 145 or later for users who run the mail client.
• Verify enterprise update channels and ESR deployments to confirm patched builds are being delivered.
• Restrict execution of unmanaged or sideloaded Firefox builds through application control policies.

Patch Information

Mozilla fixed the boundary condition in Firefox 145 and Thunderbird 145. Patch details and affected component metadata are documented in Mozilla Security Advisory MFSA-2025-87 and Mozilla Security Advisory MFSA-2025-90. Administrators using enterprise policy should validate that the app.update channel is delivering the fixed build to end users.

Workarounds

• Disable WebGPU by setting dom.webgpu.enabled to false in about:config until the patched build is deployed.
• Apply enterprise policy via the Firefox policies JSON to disable WebGPU across managed fleets.
• Restrict browsing to trusted sites through proxy or DNS filtering while the fix is being rolled out.

# Configuration example: disable WebGPU via Firefox enterprise policy
# Place in distribution/policies.json under the Firefox install directory
{
  "policies": {
    "Preferences": {
      "dom.webgpu.enabled": {
        "Value": false,
        "Status": "locked"
      }
    }
  }
}