Tomcat ConnectorsWeb server / proxy · Apache
CVE-2023-41081
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.
NVD · uneditedImportant: Authentication Bypass CVE-2023-41081 The mod_jk component of Apache Tomcat Connectors in some circumstances, such as when a configuration included "JkOptions +ForwardDirectories" but the configuration did not provide explicit mounts for all possible proxied requests, mod_jk would use an implicit mapping and map the request to the first defined worker. Such an implicit mapping could result in the unintended exposure of the status worker and/or bypass security constraints configured in httpd. As of JK 1.2.49, the implicit mapping functionality has been removed and all mappings must now be via explicit configuration. Only mod_jk is affected by this issue. The ISAPI redirector is not affected. This issue affects Apache Tomcat Connectors (mod_jk only): from 1.2.0 through 1.2.48. Users are recommended to upgrade to version 1.2.49, which fixes the issue. History 2023-09-13 Original advisory 2023-09-28 Updated summary
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.
dbcve analysis · high confidenceAuthentication bypass in Apache mod_jk where implicit request mapping to the first defined worker occurs when ForwardDirectories is enabled without explicit mounts, potentially exposing the status worker or bypassing httpd security constraints.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
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.
NVD · CPE data
Tomcat ConnectorsWeb server / proxy
>= 1.2.0, < 1.2.49CVSS 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.
From the vector- Attack vector
- Network
- Complexity
- Low
- Privileges
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- None
- Availability
- None
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
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.
dbcve checksWork through these to decide whether this CVE applies to you.
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Identify mod_jk versionRun 'apachectl -M 2>/dev/null | grep jk' to confirm mod_jk is loaded, then check the version using 'jk_version' directive output or check the mod_jk.so file versionAffected if Version is 1.2.0 through 1.2.48 (the vulnerable range)
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Locate mod_jk configurationSearch for mod_jk configuration files - typically included via 'Include' directives in httpd.conf, commonly named mod_jk.conf, workers.properties, or uriworkermap.propertiesAffected if Configuration files exist and mod_jk is in use
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Check if ForwardDirectories is enabledSearch all httpd configuration files for the 'ForwardDirectories' directive using grep or similar, check if it is set to 'On' or enabledAffected if ForwardDirectories is explicitly enabled (set to On) in the configuration
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Verify explicit worker mount configurationCheck for 'JkMount' or 'JkMountCopy' directives in the configuration files - these define explicit mappings from URL paths to Tomcat workersAffected if No JkMount directives are defined, meaning the configuration relies on implicit mapping behavior
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Check for status worker exposureInspect workers.properties or the configuration for 'worker.list' and look for 'status' or 'jkstatus' workers, verify these are not accessible without authenticationAffected if A status worker is defined and is accessible without proper access controls
User is affected if mod_jk version is 1.2.0-1.2.48 AND ForwardDirectories is enabled AND there are no explicit JkMount worker mappings defined, potentially allowing unauthenticated access to the status worker or bypassing configured security constraints.
Generated from the published advisory. Verify against your own configuration.
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.
dbcve · scoped1.2.49
Upgrade to mod_jk 1.2.49 or later and audit configurations to ensure all worker mappings are explicit rather than relying on implicit behavior.
1.2.49
- 1. Identify the current mod_jk version by checking the compiled version string (e.g., via 'mod_jk.so --version' or httpd error logs)
- 2. Download Apache Tomcat Connectors 1.2.49 from the official Apache repository (e.g., https://tomcat.apache.org/download-connectors.cgi)
- 3. Replace the existing mod_jk binary (mod_jk.so on Unix/Linux or mod_jk.dll on Windows) with the new version 1.2.49
- 4. Review all JkMount directives in the httpd configuration to ensure explicit worker mappings are defined for all proxied paths
- 5. Verify there are no configurations relying on implicit mapping behavior (previously enabled by 'JkOptions +ForwardDirectories' without explicit mounts)
- 6. Test the configuration with 'httpd -t' to check for syntax errors
- 7. Reload or restart Apache HTTP Server to apply the new mod_jk binary
- 8. Verify that the status worker is no longer accessible without explicit configuration and security constraints are enforced
Generated from the published advisory — verify against the referenced sources before acting.
Fix this in Tomcat Connectors
Scoped from the published advisory
- Consultation3.0 h
- Implementation6.0 h
- Testing3.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,984.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2023-41081 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2023-41081 in production — separate from our analysis above.
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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