FirefoxWeb browser · Mozilla

CVE-2009-0776

HIGH · 7.1 CVSS v2.0 Published 2009-03-05

Fix available

A fix is available. Upgrade to after 3.0.6 or later.

See remediation →

80/100

Remediation priority · High

Remotely reachable No privileges Zero-click

Official description

NVD · unedited

nsIRDFService in Mozilla Firefox before 3.0.7, Thunderbird before 2.0.0.21, and SeaMonkey before 1.1.15 allows remote attackers to bypass the same-origin policy and read XML data from another domain via a cross-domain redirect.

Technical summary

dbcve analysis · high confidence

The nsIRDFService component in Mozilla Firefox before 3.0.7, Thunderbird before 2.0.0.21, and SeaMonkey before 1.1.15 contains a same-origin policy bypass vulnerability. Attackers can exploit cross-domain redirects to read XML data from arbitrary domains, enabling unauthorized data theft across origins.

MitigationUpgrade affected Mozilla products to Firefox 3.0.7+, Thunderbird 2.0.0.21+, or SeaMonkey 1.1.15+ to obtain patched versions that properly enforce same-origin restrictions in nsIRDFService.

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:<= 3.0.6= 1.0= 1.0.1= 1.0.2= 1.0.3= 1.0.4= 1.0.5= 1.0.6= 1.0.7= 1.0.8= 1.5= 1.5.0.1

SeamonkeyApplication

Affected:<= 1.1.14= 1.0= 1.0.1= 1.0.2= 1.0.3= 1.0.5= 1.0.6= 1.0.7= 1.0.8= 1.0.9= 1.1= 1.1.1

ThunderbirdApplication

Affected:<= 2.0.0.20= 2.0.0.0= 2.0.0.4= 2.0.0.5= 2.0.0.6= 2.0.0.9= 2.0.0.12= 2.0.0.14= 2.0.0.16= 2.0.0.17= 2.0.0.18= 2.0.0.19

CVSS breakdown

From the vector

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

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

Am I affected?

dbcve checks

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

Identify the installed Mozilla product

Check if Firefox, Thunderbird, or SeaMonkey is installed. On Windows, look in Program Files. On Linux, check /usr/lib or /opt. On macOS, check /Applications.

Affected if Any of these three products is installed
Determine Firefox version

Open Firefox, go to Help > About Firefox, or run 'firefox --version' from command line. Record the full version number (e.g., 3.0.6).

Affected if Version is 1.0 through 1.0.8, 1.5.0.1, or 3.0.6 or earlier (any 3.0.x up to 3.0.6)
Determine Thunderbird version

Open Thunderbird, go to Help > About Thunderbird, or run 'thunderbird --version' from command line. Record the full version number.

Affected if Version is 2.0.0.0 through 2.0.0.20 inclusive (any 2.0.0.x up to 2.0.0.20)
Determine SeaMonkey version

Open SeaMonkey, go to Help > About SeaMonkey, or check installed package via system package manager. Record the full version number.

Affected if Version is 1.0 through 1.0.9, 1.1.0, 1.1.1, or 1.1.14 or earlier (any 1.1.x up to 1.1.14)

You are affected if you are running any Firefox version 1.0-1.0.8, 1.5.0.1, or 3.0-3.0.6; any Thunderbird version 2.0.0.0-2.0.0.20; or any SeaMonkey version 1.0-1.0.9, 1.1.0-1.1.1, or 1.1.14 or earlier.

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

Remediation

From vendor data

Upgrade available Upgrade to a release after 3.0.6

Interim mitigation

Upgrade affected Mozilla products to Firefox 3.0.7+, Thunderbird 2.0.0.21+, or SeaMonkey 1.1.15+ to obtain patched versions that properly enforce same-origin restrictions in nsIRDFService.

Fix this in Firefox Scoped from the published advisory

Consultation2.0 h
Implementation2.0 h
Testing1.0 h
Review / QA1.0 h

6.0 hours of engineering $1,090

Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,744.

Scan for this in your stack

Free · runs locally

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References

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2009-0776 in production — separate from our analysis above.

Notes0 Guidelines

Know something about CVE-2009-0776?

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

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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 3.0.6 or later

Severity 7.1 High

Exploit likelihood EPSS, next 30 days 1.6%

Affects: Firefox

Remediation

A high-priority fix

Fix this in Firefox 6 hrs · Low

Typical engagement from $1,090

Get a fix See the full breakdown ↓

A high-priority vulnerability. Send your environment and a specialist will scope CVE-2009-0776 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