FirefoxWeb browser · Mozilla

CVE-2012-3988

HIGH · 9.3 CVSS v2.0 Published 2012-10-10

Fix available

A fix is available. Upgrade to 10.0.8 / 16.0 or later.

See remediation →

100/100

Remediation priority · Urgent

Remotely reachable No privileges Zero-click

Official description

NVD · unedited

Use-after-free vulnerability in Mozilla Firefox before 16.0, Firefox ESR 10.x before 10.0.8, Thunderbird before 16.0, Thunderbird ESR 10.x before 10.0.8, and SeaMonkey before 2.13 might allow user-assisted remote attackers to execute arbitrary code via vectors involving use of mozRequestFullScreen to enter full-screen mode, and use of the history.back method for backwards history navigation.

Technical summary

dbcve analysis · high confidence

A use-after-free vulnerability in Mozilla Firefox, Thunderbird, and SeaMonkey allows remote attackers to execute arbitrary code via vectors involving mozRequestFullScreen to enter full-screen mode combined with history.back for backwards history navigation. The vulnerability occurs when freed memory is accessed during the history navigation after exiting full-screen mode.

MitigationUpgrade affected Mozilla products to version 16.0 or later (or ESR 10.0.8+ for supported ESR branches). Consider restricting or monitoring use of full-screen API in enterprise environments until patches are deployed.

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:< 10.0.8< 16.0

Ubuntu LinuxOperating system

Affected:= 10.04= 11.04= 11.10= 12.04

Enterprise Linux DesktopOperating system

Affected:= 5.0= 6.0

Enterprise Linux EusOperating system

Affected:= 6.3

Enterprise Linux ServerOperating system

Affected:= 5.0= 6.0

Enterprise Linux WorkstationOperating system

Affected:= 5.0= 6.0

Thunderbird EsrApplication

Affected:< 10.0.8

ThunderbirdApplication

Affected:< 16.0

CVSS breakdown

From the vector

Attack vector: Network
Complexity: M
Authentication: None
Confidentiality: Complete
Integrity: Complete
Availability: Complete

AV:N/AC:M/Au:N/C:C/I:C/A:C

Am I affected?

dbcve checks

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

Check installed Firefox version

In Firefox, go to Help > About Firefox, or run 'firefox --version' from command line. For Ubuntu/Debian, also check dpkg -l firefox or rpm -qi firefox. Compare the version to the affected ranges: < 10.0.8 or >= 10.0.8 but < 16.0

Affected if Firefox version falls below 16.0 (or below 10.0.8 for ESR) - the user is vulnerable if they browse untrusted web content
Check installed Thunderbird version

In Thunderbird, go to Help > About Thunderbird, or run 'thunderbird --version' from command line. For packaged systems, use dpkg -l thunderbird or rpm -qi thunderbird. Compare against affected ranges: < 10.0.8 or >= 10.0.8 but < 16.0

Affected if Thunderbird version falls below 16.0 (or below 10.0.8 for ESR) - the user is vulnerable when viewing HTML emails with JavaScript or browsing via Thunderbird
Verify full-screen API is accessible in Firefox

In Firefox address bar, type 'about:config' and press Enter. Search for 'fullscreen'. Check if security.fullscreen.allow-untrusted is set to true (default varies by version). Also verify javascript.enabled is not disabled

Affected if JavaScript is enabled AND full-screen API access is permitted (default) - both conditions required for exploitability
Confirm running executable is the system Firefox/Thunderbird

Check the actual binary being used: run 'which firefox' or 'which thunderbird' and verify the path matches expected system installation paths such as /usr/bin/firefox or /usr/lib/firefox/

Affected if A non-system or older portable version is in use - the version check in step 1 may not reflect the actual running binary

You are affected if you run Firefox or Thunderbird version 10.0.7 or lower, or versions 10.0.8 through 15.x, with JavaScript enabled and full-screen API accessible, and you browse untrusted web content or view HTML emails.

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

Remediation

dbcve · scoped

Upgrade available Upgrade to 10.0.8 / 16.0 or later

Fixed in 10.0.816.0

Interim mitigation

Upgrade affected Mozilla products to version 16.0 or later (or ESR 10.0.8+ for supported ESR branches). Consider restricting or monitoring use of full-screen API in enterprise environments until patches are deployed.

Recommended fix High confidence

Firefox 16.0+ (or ESR 10.0.8+), Thunderbird 16.0+ (or ESR 10.0.8+), SeaMonkey 2.13+

Upgrade Firefox to version 16.0 or later (or ESR 10.0.8 or later for extended support)
Upgrade Thunderbird to version 16.0 or later (or ESR 10.0.8 or later for extended support)
Upgrade SeaMonkey to version 2.13 or later
On Ubuntu systems, run: sudo apt-get update && sudo apt-get upgrade firefox thunderbird seamonkey
Alternatively, download latest versions from mozilla.org for your platform
Restart the application after upgrade

Caveat Some older extensions or add-ons may be incompatible with newer versions; test in non-production environment first

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

Fix this in Firefox Scoped from the published advisory

Consultation4.0 h
Implementation8.0 h
Testing6.0 h
Review / QA2.0 h

20.0 hours of engineering $3,500

Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $5,600.

Scan for this in your stack

Free · runs locally

dbcve dependency scanner

Check whether your project pulls in CVE-2012-3988 — 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

www.mozilla.orgVendor Advisory
bugzilla.mozilla.orgIssue TrackingVendor Advisory
lists.opensuse.orgThird Party Advisory
rhn.redhat.comThird Party Advisory
secunia.comThird Party Advisory
secunia.comThird Party Advisory
secunia.comThird Party Advisory
secunia.comThird Party Advisory
secunia.comThird Party Advisory
secunia.comThird Party Advisory
secunia.comThird Party Advisory
www.mandriva.comThird Party Advisory
www.ubuntu.comThird Party Advisory
exchange.xforce.ibmcloud.comThird Party AdvisoryVDB Entry
oval.cisecurity.orgThird Party Advisory
osvdb.orgBroken Link
nvd.nist.govNVD record

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2012-3988 in production — separate from our analysis above.

Notes0 Guidelines

Know something about CVE-2012-3988?

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 10.0.8 / 16.0 or later

Severity 9.3 High

Exploit likelihood EPSS, next 30 days 5.2%

Affects: Firefox

Remediation

A high-priority fix

Fix this in Firefox 20 hrs · Moderate

Typical engagement from $3,500

Get a fix See the full breakdown ↓

A high-priority vulnerability. Send your environment and a specialist will scope CVE-2012-3988 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