FirefoxWeb browser · Mozilla

CVE-2015-2743

HIGH · 7.5 CVSS v2.0 Published 2015-07-06

Fix available

A fix is available. Upgrade to after 38.1.0 or later.

See remediation →

84/100

Remediation priority · High

Remotely reachable No privileges Zero-click

Official description

NVD · unedited

PDF.js in Mozilla Firefox before 39.0 and Firefox ESR 31.x before 31.8 and 38.x before 38.1 enables excessive privileges for internal Workers, which might allow remote attackers to execute arbitrary code by leveraging a Same Origin Policy bypass.

Technical summary

dbcve analysis · moderate confidence

PDF.js in Mozilla Firefox contains a Same Origin Policy bypass vulnerability where internal Web Workers are granted excessive privileges. This allows remote attackers to potentially execute arbitrary code by leveraging the privilege escalation. Affected versions include Firefox before 39.0 and Firefox ESR 31.x before 31.8 and 38.x before 38.1.

MitigationUpgrade Firefox to version 39.0 or later, or Firefox ESR to version 31.8/38.1 or later to include the patched PDF.js component.

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:= 31.0= 31.1.0= 31.1.1= 31.3.0= 31.5.1= 31.5.2= 31.5.3= 38.0<= 38.1.0

Firefox EsrWeb browser

Affected:= 31.1= 31.2= 31.3= 31.4= 31.5= 31.6.0= 31.7.0

SolarisOperating system

Affected:= 11.3

Suse Linux Enterprise Software Development KitApplication

Affected:= 12.0

Suse Linux Enterprise DesktopOperating system

Affected:= 12.0

Suse Linux Enterprise ServerOperating system

Affected:= 11= 12.0

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 installed Firefox version

Open Firefox, navigate to about:support, or run 'firefox --version' from command line. Look for the version number in the 'Application Basics' section.

Affected if Version is less than 39.0 for standard Firefox, or version is 31.x before 31.8 for Firefox ESR 31.x, or version is 38.x before 38.1 for Firefox ESR 38.x
Confirm Firefox ESR version if applicable

If using Firefox ESR, run 'firefox --version' or check about:support to identify whether it is ESR 31.x or ESR 38.x branch.

Affected if ESR 31.x version is before 31.8, or ESR 38.x version is before 38.1
Verify PDF.js is present

Check for the presence of PDF.js in the Firefox installation directory or profile. On Windows, look in the Firefox installation folder for pdf.js; on Linux, check /usr/lib/firefox or similar paths.

Affected if PDF.js file (pdf.js or pdf.worker.js) exists in the Firefox directory and the Firefox version falls within the affected ranges from step 1
Check for affected third-party products

On Oracle Solaris 11.3 or Novell SUSE systems (Enterprise Server/Desktop/SDK 11 or 12.0), determine if Firefox is installed and obtain its version using 'firefox --version' or checking installed packages.

Affected if Firefox is installed on these platforms and its version matches the affected Firefox/Firefox ESR versions listed

Your environment is affected if Firefox or Firefox ESR is installed with a version less than 39.0, less than 31.8 (for ESR 31.x), or less than 38.1 (for ESR 38.x), and PDF.js is present in the browser installation.

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

Remediation

From vendor data

Upgrade available Upgrade to a release after 38.1.0

Interim mitigation

Upgrade Firefox to version 39.0 or later, or Firefox ESR to version 31.8/38.1 or later to include the patched PDF.js component.

Fix this in Firefox Scoped from the published advisory

Consultation1.0 h
Implementation1.0 h
Testing2.0 h
Review / QA1.0 h

5.0 hours of engineering $860

Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,376.

Scan for this in your stack

Free · runs locally

dbcve dependency scanner

Check whether your project pulls in CVE-2015-2743 — 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-2015-2743 in production — separate from our analysis above.

Notes0 Guidelines

Know something about CVE-2015-2743?

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 38.1.0 or later

Severity 7.5 High

Exploit likelihood EPSS, next 30 days 4.7%

Affects: Firefox

Remediation

A high-priority fix

Fix this in Firefox 5 hrs · Low

Typical engagement from $860

Get a fix See the full breakdown ↓

A high-priority vulnerability. Send your environment and a specialist will scope CVE-2015-2743 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