TomcatWeb server / proxy · Apache

CVE-2012-0022

MEDIUM · 5.0 CVSS v2.0 Published 2012-01-19

Mitigation only

No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.

See remediation →

59/100

Remediation priority · Elevated

Remotely reachable No privileges Zero-click

Official description

NVD · unedited

Apache Tomcat 5.5.x before 5.5.35, 6.x before 6.0.34, and 7.x before 7.0.23 uses an inefficient approach for handling parameters, which allows remote attackers to cause a denial of service (CPU consumption) via a request that contains many parameters and parameter values, a different vulnerability than CVE-2011-4858.

Technical summary

dbcve analysis · high confidence

Apache Tomcat versions 5.5.x before 5.5.35, 6.x before 6.0.34, and 7.x before 7.0.23 use an inefficient algorithm for parsing HTTP request parameters. When a request contains many parameters and parameter values, the parameter handling code executes in O(n²) time complexity, causing excessive CPU consumption that can lead to denial of service.

MitigationUpgrade to Tomcat 5.5.35+, 6.0.34+, or 7.0.23+ or later. As a compensating control, consider implementing request rate limiting or Web Application Firewall rules to block requests with unusually high parameter counts.

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

TomcatWeb server / proxy

Affected:= 5.5.0= 5.5.1= 5.5.2= 5.5.3= 5.5.4= 5.5.5= 5.5.6= 5.5.7= 5.5.8= 5.5.9= 5.5.10= 5.5.11

CVSS breakdown

From the vector

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

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

Am I affected?

dbcve checks

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

Identify Tomcat installation location

Locate the Tomcat installation directory, typically found in /opt/apache-tomcat, /usr/share/tomcat, or C:\Program Files\Apache Software Foundation\Tomcat on Windows. Check for the presence of the 'bin' and 'lib' directories containing Tomcat files.

Affected if Tomcat is installed in any of these common locations.
Determine installed Tomcat version

Check the RELEASE-NOTES file in the Tomcat installation root or run 'catalina.sh version' (or 'catalina.bat version' on Windows) from the bin directory. The version number will be displayed in the output.

Affected if The version cannot be determined or the RELEASE-NOTES file is missing.
Compare version against affected ranges

If running Tomcat 5.5.x, ensure the version is 5.5.35 or later. For Tomcat 6.x, ensure 6.0.34 or later. For Tomcat 7.x, ensure 7.0.23 or later. Any version lower than these thresholds is affected.

Affected if The installed version is 5.5.x below 5.5.35, OR 6.x below 6.0.34, OR 7.x below 7.0.23.
Confirm the server processes HTTP parameters

Verify the Tomcat instance is configured to handle HTTP requests with query parameters. This is the default behavior for any web application deployed on Tomcat accepting GET or POST requests.

Affected if The Tomcat server accepts HTTP requests containing query parameters, which is the standard operating mode.

A user is affected if their Tomcat installation version falls below 5.5.35 (for 5.5.x), below 6.0.34 (for 6.x), or below 7.0.23 (for 7.x), and the server processes HTTP requests with parameters.

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

Remediation

From vendor data

Mitigation available No clean upgrade yet — mitigate in the meantime

Mitigation

Upgrade to Tomcat 5.5.35+, 6.0.34+, or 7.0.23+ or later. As a compensating control, consider implementing request rate limiting or Web Application Firewall rules to block requests with unusually high parameter counts.

Fix this in Tomcat Scoped from the published advisory

Consultation4.0 h
Implementation4.0 h
Testing8.0 h
Review / QA2.0 h

18.0 hours of engineering $3,080

Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $4,928.

Scan for this in your stack

Free · runs locally

dbcve dependency scanner

Check whether your project pulls in CVE-2012-0022 — 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-2012-0022 in production — separate from our analysis above.

Notes0 Guidelines

Know something about CVE-2012-0022?

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 existsA vendor remedy is published

Severity 5.0 Medium

Exploit likelihood EPSS, next 30 days 10.9%

Affects: Tomcat

Remediation

Need this fixed?

Fix this in Tomcat 18 hrs · Low

Typical engagement from $3,080

Get a fix See the full breakdown ↓

We specialise in CVE remediation. Send your environment and we’ll scope CVE-2012-0022 and return a fixed quote.

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