How severe is CVE-2014-0099?

No CVSS score has been assigned to CVE-2014-0099 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by CVE-2014-0099?

CVE-2014-0099 affects the following packages: org.apache.tomcat:tomcat (Maven), org.apache.tomcat:tomcat (Maven), org.apache.tomcat:tomcat (Maven), org.apache.tomcat:tomcat-util (Maven), org.apache.tomcat:tomcat-util (Maven), org.apache.tomcat:tomcat-util (Maven). Ecosystems affected: Maven.

How do I fix CVE-2014-0099?

Update org.apache.tomcat:tomcat to 6.0.40 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2014-0099 is resolved across your whole dependency graph.

How do I detect CVE-2014-0099 in my Maven dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.apache.tomcat:tomcat, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2014-0099 if there is no patch (or I can't update yet)?

Constrain what reaches the vulnerable code: limit the size and shape of untrusted input, isolate the affected component in a sandboxed or least-privileged process, and enable the platform's memory-safety mitigations (ASLR, stack protector, hardened allocator) so an out-of-bounds access is more likely to fail closed than to be exploitable.

Is CVE-2014-0099 actively exploited in the wild?

No public exploit code has been indexed for CVE-2014-0099 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2014-0099?

CVE-2014-0099 has an EPSS (Exploit Prediction Scoring System) score of 8.8%, placing it in the 95th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2014-0099?

CVE-2014-0099 is classified as CWE-189 (CWE-189). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2014-0099 published, and has it been updated?

CVE-2014-0099 was published on May 14, 2022 and was last updated on April 14, 2025. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

☕ Maven

Not in CISA KEV

CVE-2014-0099 — tomcat

Fix: apache/tomcat@184cdc0

CVE-2014-0099 is a CWE-189 vulnerability in org.apache.tomcat:tomcat. A fix is available for org.apache.tomcat:tomcat — see the affected versions and patch details below.

Improper Neutralization of CRLF Sequences in HTTP Headers in Apache Tomcat

Published

May 14, 2022

Updated

Apr 14, 2025

Affected

6 pkgs

Patched

6 / 6

Exploits

None indexed

Exploitation data as of Nov 4, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for CVE-2014-0099.

EPSS Exploitation Probability

via FIRST.org ↗

8.8%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs95th percentile — riskier than 95% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

Real-World Exposure

6 pkgs affected

☕org.apache.tomcat:tomcat☕org.apache.tomcat:tomcat☕org.apache.tomcat:tomcat☕org.apache.tomcat:tomcat-util☕org.apache.tomcat:tomcat-util☕org.apache.tomcat:tomcat-util

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.

Description

Integer overflow in java/org/apache/tomcat/util/buf/Ascii.java in Apache Tomcat before 6.0.40, 7.x before 7.0.53, and 8.x before 8.0.4, when operated behind a reverse proxy, allows remote attackers to conduct HTTP request smuggling attacks via a crafted Content-Length HTTP header.

Affected Packages

6 total 6 fixed

Ecosystem	Package	Vulnerable range	Fix
☕Maven	`org.apache.tomcat:tomcat`	all versions	6.0.40`org.apache.tomcat:tomcat:6.0.40`
☕Maven	`org.apache.tomcat:tomcat`	≥ 7.0.0&&< 7.0.54	7.0.54`org.apache.tomcat:tomcat:7.0.54`
☕Maven	`org.apache.tomcat:tomcat`	≥ 8.0.0&&< 8.0.6	8.0.6`org.apache.tomcat:tomcat:8.0.6`
☕Maven	`org.apache.tomcat:tomcat-util`	all versions	6.0.40`org.apache.tomcat:tomcat-util:6.0.40`
☕Maven	`org.apache.tomcat:tomcat-util`	≥ 7.0.0&&< 7.0.54	7.0.54`org.apache.tomcat:tomcat-util:7.0.54`
☕Maven	`org.apache.tomcat:tomcat-util`	≥ 8.0.0&&< 8.0.6	8.0.6`org.apache.tomcat:tomcat-util:8.0.6`

Affected Products

1 product · 107 configurations

Application

tomcatapache

≤ 6.0.39

90 versions

66.06.0.06.0.16.0.26.0.36.0.46.0.56.0.66.0.76.0.86.0.9

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.apache.tomcat:tomcat, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update org.apache.tomcat:tomcat to 6.0.40 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2014-0099 is resolved across your whole dependency graph.
Workarounds
Constrain what reaches the vulnerable code: limit the size and shape of untrusted input, isolate the affected component in a sandboxed or least-privileged process, and enable the platform's memory-safety mitigations (ASLR, stack protector, hardened allocator) so an out-of-bounds access is more likely to fail closed than to be exploitable.

Fixing This On Your OS

If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.

Red HatModerate

This issue does affect JBossWeb as shipped in Red Hat JBoss Enterprise Application Platform 5. Red Hat Product Security has rated this issue as having Moderate security impact. Red Hat JBoss Enterprise Application Platform 5 is currently in reduced support phase (Phase 2: Maintenance Support), receiving only Critical…

Product	Fixed in	Advisory
Red Hat Enterprise Linux 6	`tomcat6-0:6.0.24-72.el6_5`	RHSA-2014:0865
Red Hat Enterprise Linux 7	`tomcat-0:7.0.42-6.el7_0`	RHSA-2014:0827
Red Hat JBoss BPMS 6.0	`jbossweb`	RHSA-2015:0234
Red Hat JBoss BRMS 6.0	`jbossweb`	RHSA-2015:0235
Red Hat JBoss Data Grid 6.3	`jbossweb`	RHSA-2014:0895
Red Hat JBoss Data Virtualization 6.0	`jbossweb`	RHSA-2015:0765
Red Hat JBoss Data Virtualization 6.1	see advisory	RHSA-2015:0675
Red Hat JBoss Enterprise Application Platform 6.2	see advisory	RHSA-2014:0842

Frequently Asked Questions

O3 Security · Impact-Aware SCA

Is CVE-2014-0099 in your dependencies?

Find it across Maven, including transitive dependencies.

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