---
id: "CVE-2026-117863"
kind: "vulnerability"
aliases: ["CVE-2026-117863"]
title: "Firefox: uninitialized memory in Audio/Video leaks data to attackers"
severity: "unknown"
cvss: null
epss: null
exploited: false
status: "open"
category: "runtime"
products: []
ecosystems: []
tags: ["browsers", "desktop", "firefox", "runtime"]
not_affected_if: ["already-patched-version"]
published_at: "2026-10-27T14:16:40+00:00"
first_seen_at: "2026-10-27T14:32:21+00:00"
updated_at: "2026-10-27T14:39:22+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-117863", "first_seen_at": "2026-10-27T14:32:21+00:00"}]
---

# Firefox: uninitialized memory in Audio/Video leaks data to attackers

Firefox's Audio/Video component can expose uninitialized memory, which can leak fragments of other process data. The sources do not describe the exact trigger, so the attacker's reach beyond information disclosure is unknown.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Run `firefox --version` (or check the About Firefox page) and compare against the fixed versions
- Check ESR installs for `115.44` or `153.6` or later
- unknown for other checks, as the sources do not say

## Fix

- Update Firefox to `159` or later
- Update Firefox ESR 115 to `115.44` or later
- Update Firefox ESR 153 to `153.6` or later

## Timeline

- 2026-10-27T14:32:21+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-117863

## From the sources

Information disclosure due to uninitialized memory in the Audio/Video component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, and Firefox ESR 153.6.

---

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