Apache Tomcat 7.x through 7.0.70 and 8.x through 8.5.4, when the CGI Servlet is enabled, follows RFC 3875 section 4.1.18 and therefore…

Description

Apache Tomcat 7.x through 7.0.70 and 8.x through 8.5.4, when the CGI Servlet is enabled, follows RFC 3875 section 4.1.18 and therefore does not protect applications from the presence of untrusted client data in the HTTP_PROXY environment variable, which might allow remote attackers to redirect an application's outbound HTTP traffic to an arbitrary proxy server via a crafted Proxy header in an HTTP request, aka an "httpoxy" issue. NOTE: the vendor states "A mitigation is planned for future releases of Tomcat, tracked as CVE-2016-5388"; in other words, this is not a CVE ID for a vulnerability.

Scores

EPSS (exploitation in 30 days)

50.9% · top 1.1% of all CVEs (3 Nov 2026)

CISA SSVC

Exploitation: none · Automatable: no · Technical impact: partial

Loading the EPSS history…

The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.1.

Weakness

• n/a
• CWE-284 (opens in a new tab)Other CVEs with CWE-284

Affected products

• n/a

  • affected n/a

Affected packages

From reviewed advisories of the GitHub Advisory Database.

• Mavenorg.apache.tomcat:tomcat-catalinaGHSA-v646-rx6w-r3qq (opens in a new tab)

References (25)

• RHSA-2016:1635 (opens in a new tab)vendor-advisoryx_refsource_REDHATx_transferred
• https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05320149 (opens in a new tab)x_refsource_CONFIRMx_transferred
• https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05324759 (opens in a new tab)x_refsource_CONFIRMx_transferred
• VU#797896 (opens in a new tab)third-party-advisoryx_refsource_CERT-VNx_transferred
• http://www.oracle.com/technetwork/topics/security/linuxbulletinoct2016-3090545.html (opens in a new tab)x_refsource_CONFIRMx_transferred
• RHSA-2016:2045 (opens in a new tab)vendor-advisoryx_refsource_REDHATx_transferred
• RHSA-2016:2046 (opens in a new tab)vendor-advisoryx_refsource_REDHATx_transferred
• https://tomcat.apache.org/tomcat-7.0-doc/changelog.html (opens in a new tab)x_refsource_CONFIRMx_transferred
• 91818 (opens in a new tab)vdb-entryx_refsource_BIDx_transferred
• openSUSE-SU-2016:2252 (opens in a new tab)vendor-advisoryx_refsource_SUSEx_transferred
• https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05390722 (opens in a new tab)x_refsource_CONFIRMx_transferred
• https://h20566.www2.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbhf03770en_us (opens in a new tab)x_refsource_CONFIRMx_transferred
• RHSA-2016:1624 (opens in a new tab)vendor-advisoryx_refsource_REDHATx_transferred
• https://www.apache.org/security/asf-httpoxy-response.txt (opens in a new tab)x_refsource_CONFIRMx_transferred
• https://httpoxy.org/ (opens in a new tab)x_refsource_MISCx_transferred
• http://www.oracle.com/technetwork/security-advisory/cpujul2017-3236622.html (opens in a new tab)x_refsource_CONFIRMx_transferred
• 1036331 (opens in a new tab)vdb-entryx_refsource_SECTRACKx_transferred
• RHSA-2016:1636 (opens in a new tab)vendor-advisoryx_refsource_REDHATx_transferred
• [debian-lts-announce] 20190813 [SECURITY] [DLA 1883-1] tomcat8 security update (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
• [activemq-issues] 20190820 [jira] [Created] (AMQ-7279) Security Vulnerabilities in Libraries - jackson-databind-2.9.8.jar, tomcat-servlet-api-8.0.53.jar, tomcat-websocket-api-8.0.53.jar, zookeeper-3.4.6.jar, guava-18.0.jar, jetty-all-9.2.26.v20180806.jar, scala-library-2.11.0.jar (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
• [activemq-issues] 20190826 [jira] [Created] (AMQ-7288) Security Vulnerabilities in ActiveMQ dependent libraries. (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
• [activemq-issues] 20190925 [jira] [Created] (AMQ-7310) Security Vulnerabilities in Tomcat-websocket-api.jar (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
• [tomcat-users] 20200813 CVE reporting discrepencies (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
• [tomcat-users] 20200813 Re: CVE reporting discrepencies (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
• [tomcat-users] 20200814 Re: CVE reporting discrepencies (opens in a new tab)mailing-listx_refsource_MLISTx_transferred

Sources

The same CVE in the primary databases and aggregators, to check against.

• CVE.org record (opens in a new tab)
• CVE List JSON (GitHub) (opens in a new tab)
• NVD (opens in a new tab)
• FIRST EPSS (opens in a new tab)
• OSV.dev (opens in a new tab)
• GitHub Advisory GHSA-v646-rx6w-r3qq (opens in a new tab)
• CIRCL Vulnerability-Lookup (opens in a new tab)

Badge for a README or a ticket

[![CVE-2016-5388](https://trackcve.app/badge/CVE-2016-5388.svg)](https://trackcve.app/cve/CVE-2016-5388)

Record last updated 15 Oct 2026, 15:48 UTC.