Vulnerability report

Exploited in the wild High confidence Not in CISA KEV

CVE-2018-11759

Apache Tomcat Connectors

Apache Tomcat Connectors · Apache Tomcat JK (mod_jk) Connector 1.2.0 to 1.2.44

Watch CVE-2018-11759 Browse KEV feed
Severity
CVSS 7.5 · High
Confidence
High
Exploit status
Exploited in the wild
EPSS
90.6%
First observed
—
Last observed
—

Decision summary

What security teams need to know first

Direct answers before the deeper technical record.

What it is

CVE-2018-11759 is an unauthenticated vulnerability affecting Apache Tomcat Connectors. The Apache Web Server (httpd) specific code that normalised the requested path before matching it to the URI-worker map in Apache...

Is it exploited?

Yes. Previdian tracks this CVE as a known exploited vulnerability. Confidence is high. Also confirmed by third-party sources.

Who is affected?

Apache Tomcat Connectors apache tomcat jk (mod_jk) connector 1.2.0 to 1.2.44.

What should we do?

Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.

Overview

Apache Tomcat Connectors

The Apache Web Server (httpd) specific code that normalised the requested path before matching it to the URI-worker map in Apache Tomcat JK (mod_jk) Connector 1.2.0 to 1.2.44 did not handle some edge cases correctly. If only a sub-set of the URLs supported by Tomcat were exposed via httpd, then it was possible for a specially constructed request to expose application functionality through the reverse proxy that was not intended for clients accessing the application via the reverse proxy.

It was also possible in some configurations for a specially constructed request to bypass the access controls configured in httpd. While there is some overlap between this issue and CVE-2018-1323, they are not identical.

Apache Software Foundation Affected
Apache Tomcat Connectors
Apache Tomcat JK (mod_jk) Connector 1.2.0 to 1.2.44
View vendor advisory (opens in new tab)
Published
31 Oct 2018
Exploitation Reported
24 Apr 2025
Attack vector
Remote
Complexity
Low
Privileges
None
User interaction
None

Tags

nuclei_scanner apache

CVE References

Exploitation evidence

Why Previdian marks this CVE as exploited

Third-party attestation and first-party sensor observation are shown separately so teams can judge the evidence chain.

Exploited in the wild

The Shadowserver

Recorded 24 Apr 2025

A trusted third party reported exploitation.

Proof of concept available

GitHub

Recorded 01 Nov 2018

Public scanner or PoC coverage increases practical exploitability.

Known exploited vulnerability sources

Per-source evidence links for KEV attestations are available through the Previdian Pro API.

Learn about Pro API access
Source Added
The Shadowserver First 2025-04-24 00:00 UTC

Detection

Operational artifacts and observed signals

Make the evidence actionable in scanner, SOC, and edge-control workflows.

Observed signals

Request targets
User-Agents
Callback hosts
0
0
0

Request targets and User-Agents available in Pro. Callback host details available in Enterprise.

Virtual patch status

No Previdian virtual patch is currently available. Future rules ship for ModSecurity, Cloudflare, and AWS WAF.

Learn about virtual patches →

Scanner Artifacts

Scanner and exploit-framework references linked to this CVE.

Scanner Reference Detected
Nuclei https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2018/CVE-2018-11759.yaml 25 Apr 2025

Risk and context

Severity, weaknesses, and research context

CVSS v3.0

7.5 High

Potential damage if exploited. Separate from whether attackers are using it.

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

EPSS

90.6%

Estimated chance of exploitation in the next 30 days. Previdian's warning comes from evidence, not this score.

Weaknesses

Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') CWE-22

All CVSS Scores

CVSS v3.0 7.5 High

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

CVSS v2.0 5.0 Medium

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

Potential Proof of Concepts

These PoCs are unverified and could contain malware. Use at your own risk.

Apache Tomcat JK Connect <=1.2.44 - Manager Access

nuclei · Created Unknown

Timeline

From disclosure to observed exploitation

  1. 14:20 UTC

    Public PoC available

    Public proof-of-concept code published

  2. 00:00 UTC

    Nuclei template available

    Scanner coverage available

  3. 00:00 UTC

    Added to Previdian KEV Feed

    High-confidence, third-party attested exploitation

  4. 20:00 UTC

    CVE published

    Vulnerability disclosed publicly

  5. 00:00 UTC

    CVE ID reserved

    Identifier reserved by the CNA

Pro API

Automate this intelligence

Confidence, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.

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  • Evidence confidence and provenance
  • First-party sensor telemetry
  • PoC and scanner references
  • Affected versions and enrichment
  • Automation-ready JSON delivery

GET /api/v2/pro/kevs/CVE-2018-11759

Free JSON includes basic KEV fields 
{
  "cve_id": "CVE-2018-11759",
  "confidence": "High",
  "cvss_score": 7.5,
  "cvss_estimated": false,
  "epss_score": 0.90647,
  "exploit_status": {
    "exploited_in_the_wild": true,
    "active_exploitation_observed": false
  },
  "sensor_telemetry": { "attempts": 0, "sensors": 0 }
}