CVE-2018-11759
HighExploitedThe 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.
Published Oct 31, 2018 · Updated Aug 4, 2026 · Also known as DEBIAN-CVE-2018-11759, DLA-1609-1, DSA-4357-1, SUSE-SU-2018:3963-2, SUSE-SU-2018:3969-1, SUSE-SU-2023:4513-1, UBUNTU-CVE-2018-11759
Key Facts
Patch immediately- CVE-2018-11759 is a high-severity vulnerability (CVSS 7.5 v3.1) affecting Tomcat Jk Connector (Apache), Jboss Core Services (Redhat), Debian Linux and 12 more products.
- It is exploited in the wild, listed in Industry KEV feed, CIRCL KEV since Dec 19, 2023. No public exploit code is known.
- EPSS estimates a 91% probability of exploitation in the next 30 days.
- Fixed versions are available, including Tomcat Jk Connector <=1.2.44, apache2-mod_jk 1.2.40-0.2.5.1, apache2-mod_jk 1.2.40-7.3.1.
- Brandefense priority: patch immediately, because it is listed as exploited in the wild.
CVSS v3.1
7.5
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
EPSS (30-day exploit likelihood)
91%
Higher than 99.8% of all scored CVEs
Exploited in the wild
Yes
2 catalog listings
Public exploit code
None known
Get the full CVE-2018-11759 brief as a PDF
Every affected product and fixed release, exploitation status and a first 24 hours response checklist, emailed within minutes.
Description
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.
Known-Exploited Catalog Listings
| Catalog | Added | Remediation due | Ransomware use |
|---|---|---|---|
| Industry KEV feed | Dec 19, 2023 | n/a | Not reported |
| CIRCL KEV | Dec 19, 2023 | n/a | Not reported |
Required action: Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.
Affected Products
56 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| Tomcat Jk ConnectorApache | See advisory | 1.2.44 |
| Jboss Core ServicesRedhat | See advisory | n/a |
| Debian LinuxDebian | 8.0, 9.0 | n/a |
| libapache-mod-jkdebian | See advisory | 1:1.2.46-1 |
| apache2-mod_jksuse | See advisory | 1.2.49-150100.6.6.1 |
Patched Releases
Tomcat Jk Connector
<=1.2.44
apache2-mod_jk
1.2.40-0.2.5.1, 1.2.40-7.3.1, 1.2.43-3.3.1, 1.2.43-lp150.2.3.1, 1.2.48-2.9, 1.2.49-150100.6.6.1
jbcs-httpd24
0:1-6.jbcs.el6, 0:1-6.jbcs.el7
jbcs-httpd24-apache-commons-daemon-jsvc
1:1.1.0-3.redhat_2.jbcs.el6, 1:1.1.0-3.redhat_2.jbcs.el7
jbcs-httpd24-apr
0:1.6.3-31.jbcs.el6, 0:1.6.3-31.jbcs.el7
jbcs-httpd24-apr-util
0:1.6.1-24.jbcs.el6, 0:1.6.1-24.jbcs.el7
jbcs-httpd24-httpd
0:2.4.29-35.jbcs.el6, 0:2.4.29-35.jbcs.el7
jbcs-httpd24-mod_cluster-native
0:1.3.8-3.Final_redhat_2.jbcs.el6, 0:1.3.8-3.Final_redhat_2.jbcs.el7
jbcs-httpd24-mod_jk
0:1.2.46-1.redhat_1.jbcs.el6, 0:1.2.46-1.redhat_1.jbcs.el7
jbcs-httpd24-nghttp2
0:1.29.0-9.jbcs.el6, 0:1.29.0-9.jbcs.el7
jbcs-httpd24-openssl
1:1.0.2n-14.jbcs.el6, 1:1.0.2n-14.jbcs.el7
libapache-mod-jk
1:1.2.46-0+deb8u1, 1:1.2.46-0+deb9u1, 1:1.2.46-1
Timeline
Publicly disclosed
Oct 31, 2018
Added to Industry KEV feed
Dec 19, 2023
Added to CIRCL KEV
Dec 19, 2023
Last updated
Aug 4, 2026
Weakness Type
- CWE-22 Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
References
- advisoryRHSA-2019:0366
- advisoryRHSA-2019:0367
- advisoryhttps://bugzilla.suse.com/1114612
- advisoryhttps://bugzilla.suse.com/927845
- advisoryhttps://lists.apache.org/thread.html/6d564bb0ab73d6b3efdd1d6b1c075d1a2c84ecd84a4159d6122529ad@%3Cannounce.tomcat.apache.org%3E
FAQ
Common Questions.
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.
Affected: Tomcat Jk Connector (Apache); Jboss Core Services (Redhat); Debian Linux versions 8.0, 9.0, among others. The full list is in the CVE brief.
It is exploited in the wild, listed in Industry KEV feed, CIRCL KEV since Dec 19, 2023.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
No public exploit code is known.
Fixed versions are available, including Tomcat Jk Connector <=1.2.44, apache2-mod_jk 1.2.40-0.2.5.1, apache2-mod_jk 1.2.40-7.3.1.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.
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