FirefoxWeb browser · Mozilla

CVE-2015-7200

HIGH · 7.5 CVSS v2.0 Published 2015-11-05

Fix available

A fix is available. Upgrade to after 41.0.2 or later.

See remediation →

84/100

Remediation priority · High

Remotely reachable No privileges Zero-click

Official description

NVD · unedited

The CryptoKey interface implementation in Mozilla Firefox before 42.0 and Firefox ESR 38.x before 38.4 lacks status checking, which allows attackers to have an unspecified impact via vectors related to a cryptographic key.

Technical summary

dbcve analysis · moderate confidence

The CryptoKey interface implementation in Mozilla Firefox before 42.0 and Firefox ESR 38.x before 38.4 lacks proper status checking, which could allow attackers to manipulate cryptographic key operations by leveraging the missing validation during key handling.

MitigationUpgrade to Firefox 42.0 or later, or Firefox ESR 38.4 or later to obtain the patched version with proper status checking in the CryptoKey interface.

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

Affected products & versions

NVD · CPE data

FirefoxWeb browser

Affected:<= 41.0.2= 38.0= 38.0.1= 38.0.5= 38.1.0= 38.1.1= 38.2.0= 38.2.1= 38.3.0

CVSS breakdown

From the vector

Attack vector: Network
Complexity: Low
Authentication: None
Confidentiality: Partial
Integrity: Partial
Availability: Partial

AV:N/AC:L/Au:N/C:P/I:P/A:P

Am I affected?

dbcve checks

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

Check Firefox version number

Open Firefox, click the menu button (three horizontal lines), select Help, then About Firefox. The version number is displayed in the window that opens.

Affected if The version listed is 41.0.2 or lower, or any version 38.x that is 38.3.0 or lower (for ESR)
Confirm if using Firefox ESR

In the About Firefox window, look for 'Firefox ESR' or 'Extended Support Release' in the version string. If it says just 'Firefox' without ESR, it is the regular release.

Affected if The installed version is Firefox ESR 38.0 through 38.3.0 (38.x where x is less than 4)
Identify Web Crypto API usage

Check if any web applications or add-ons installed in the browser are using the Web Crypto API (window.crypto.subtle) for cryptographic key operations. Review installed add-ons and any custom web applications that may access cryptographic functions.

Affected if Web applications or add-ons rely on window.crypto.subtle for key generation, encryption, or signing operations while running on a vulnerable Firefox version
Verify CryptoKey object handling

If you develop or test web applications, review any code that creates or manipulates CryptoKey objects. Look for code paths that handle key.status without proper validation before cryptographic operations.

Affected if Custom code uses CryptoKey objects and the browser version falls within the affected range

A user is affected if they run Firefox 41.0.2 or earlier, or Firefox ESR 38.0 through 38.3.0, AND their browser or any web application uses the Web Crypto API for cryptographic key operations.

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

Remediation

From vendor data

Upgrade available Upgrade to a release after 41.0.2

Interim mitigation

Upgrade to Firefox 42.0 or later, or Firefox ESR 38.4 or later to obtain the patched version with proper status checking in the CryptoKey interface.

Fix this in Firefox Scoped from the published advisory

Consultation2.0 h
Implementation3.0 h
Testing3.0 h
Review / QA2.0 h

10.0 hours of engineering $1,750

Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,800.

Scan for this in your stack

Free · runs locally

dbcve dependency scanner

Check whether your project pulls in CVE-2015-7200 — 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

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2015-7200 in production — separate from our analysis above.

Notes0 Guidelines

Know something about CVE-2015-7200?

The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.

The version that genuinely resolved it — not the one the vendor claimed
A config change or rule that shut the vector down
A gotcha in the upgrade path that cost you an afternoon

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

At a glance

A fix existsUpgrade to after 41.0.2 or later

Severity 7.5 High

Exploit likelihood EPSS, next 30 days 2.1%

Affects: Firefox

Remediation

A high-priority fix

Fix this in Firefox 10 hrs · Moderate

Typical engagement from $1,750

Get a fix See the full breakdown ↓

A high-priority vulnerability. Send your environment and a specialist will scope CVE-2015-7200 and return a fixed quote and timeline.

You’ll deal with our team directly and deploy the reviewed fix to staging first — never straight to production.

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.

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.

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.

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.

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.

Check your environment

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.

Scan for this in your stack

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

Practitioner notes

No notes yet

Official description

Technical summary

Affected products & versions

CVSS breakdown

Am I affected?

Remediation

References