dbcve.org
FirefoxWeb browser · Mozilla

CVE-2020-15684

CRITICAL · 9.8 CVSS v3.1 Published 2020-10-22
Fix available
A fix is available. Upgrade to 82.0 or later.
See remediation →
100/100
Remediation priority · Urgent
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
Mozilla developers reported memory safety bugs present in Firefox 81. 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 affects Firefox < 82.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

Memory safety bugs in Firefox versions prior to 82 could lead to memory corruption. Mozilla developers identified vulnerabilities that with sufficient effort could be exploited to execute arbitrary code.

MitigationUpgrade Firefox to version 82 or later to apply Mozilla's memory safety fixes.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
FirefoxWeb browser
Affected:< 82.0

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Determine installed Firefox version
    Open terminal or command prompt and run 'firefox --version' or 'firefox -v'. Alternatively, launch Firefox, click the menu (three horizontal lines), then click Help > About Firefox.
    Affected if The version shown is less than 82.0 (for example, 81.0, 80.0, 79.0, etc.)
  2. Confirm the exact version number
    In the About Firefox window or command output, note the full version string (e.g., 81.0.1, 81.0, 80.0.2). Compare the numeric version to 82.0.
    Affected if Any version where the major number is 81 or lower, regardless of minor/patch numbers.

If the installed Firefox version is below 82.0, the environment is vulnerable to the memory safety issues described in CVE-2020-15684.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 82.0 or later
Fixed in 82.0
Interim mitigation

Upgrade Firefox to version 82 or later to apply Mozilla's memory safety fixes.

Recommended fix High confidence

Firefox 82.0 or later

  1. Back up any important browser data such as bookmarks, saved passwords, and preferences
  2. Navigate to the official Mozilla Firefox download page at https://www.mozilla.org/firefox/
  3. Download and install Firefox version 82.0 or later
  4. After installation, verify the version by navigating to Help > About Firefox
  5. Ensure the version displayed is 82.0 or higher

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Firefox Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing2.0 h
  • Review / QA1.0 h
9.0 hours of engineering $1,600
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,560.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2020-15684 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2020-15684 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data