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Fencer Vulns
medium 6.1

CVE-2016-4993 json

Improper Neutralization of CRLF Sequences in Wildfly Undertow

published 2016-09-26 10 y ago modified 2026-06-17 4 mo ago also GHSA-qcqr-hcjq-whfq , EUVD-2022-4951

cvss
6.1
version 3.0, NVD
cisa kev
Not listed
not in CISA's catalog
epss
2.5%
EPSS 2.5% chance of exploitation in 30 days, percentile 85%
public exploits
0
none known

Summary

CRLF injection vulnerability in the Undertow web server in WildFly 10.0.0, as used in Red Hat JBoss Enterprise Application Platform (EAP) 7.x before 7.0.2, allows remote attackers to inject arbitrary HTTP headers and conduct HTTP response splitting attacks via unspecified vectors.

Patch / fix

  • maven org.wildfly:wildfly-undertow 11.0.0.Final
  • undertow Debian 14 1.4.3-1

debian advisories DEBIAN-CVE-2016-4993

  • eap7-jboss-ec2-eap jboss enterprise application platform 7 7.1.0-5.GA_redhat_5.ep7.el6
  • eap7-jboss-ec2-eap jboss enterprise application platform 7.1 7.1.0-5.GA_redhat_5.ep7.el7
  • eap7-jboss-ec2-eap-samples jboss enterprise application platform 7 7.1.0-5.GA_redhat_5.ep7.el6
  • eap7-jboss-ec2-eap-samples jboss enterprise application platform 7.1 7.1.0-5.GA_redhat_5.ep7.el7
  • eap7-ecj jboss enterprise application platform 7.1 4.6.1-1.redhat_1.1.ep7.el7
  • eap7-vdx jboss enterprise application platform 7.1 1.1.6-1.redhat_1.1.ep7.el7
  • eap7-xom jboss enterprise application platform 7.1 1.2.10-2.redhat_1.1.ep7.el7
  • eap7-txw2 jboss enterprise application platform 7.1 2.2.11-10.redhat_4.1.ep7.el7

red hat advisories RHSA-2017:3458RHSA-2017:3455RHSA-2017:3454RHSA-2016:1840RHSA-2016:1839RHSA-2016:1838

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2016-4993 updated cvss 5.4

eap: HTTP header injection / response splitting

  • Red Hat JBoss EAP 7.0
    fixed: vendor fix RHSA-2016:1841
  • Red Hat JBoss EAP 7.1
    fixed: vendor fix RHSA-2017:3456
  • Red Hat JBoss Enterprise Application Platform 7.0 for RHEL 6 Server eap7-wss4j 2.1.5-1.redhat_1.1.ep7.el6, eap7-apache-cxf 3.1.6-1.redhat_1.1.ep7.el6, eap7-wildfly 7.0.2-2.GA_redhat_1.1.ep7.el6, eap7-xalan-j2 2.7.1-25.redhat_11.1.ep7.el6, eap7-jberet 1.2.1-1.Final_redhat_1.1.ep7.el6, eap7-wss4j-policy 2.1.5-1.redhat_1.1.ep7.el6, +68 more
    fixed: vendor fix RHSA-2016:1838
  • Red Hat JBoss Enterprise Application Platform 7.0 for RHEL 7 Server eap7-wss4j 2.1.5-1.redhat_1.1.ep7.el7, eap7-apache-cxf 3.1.6-1.redhat_1.1.ep7.el7, eap7-wildfly 7.0.2-2.GA_redhat_1.1.ep7.el7, eap7-xalan-j2 2.7.1-25.redhat_11.1.ep7.el7, eap7-jberet 1.2.1-1.Final_redhat_1.1.ep7.el7, eap7-wss4j-policy 2.1.5-1.redhat_1.1.ep7.el7, +68 more
    fixed: vendor fix RHSA-2016:1840
  • Red Hat JBoss Enterprise Application Platform 7.1 for RHEL 6 Server eap7-ecj 4.6.1-1.redhat_1.1.ep7.el6, eap7-vdx 1.1.6-1.redhat_1.1.ep7.el6, eap7-xom 1.2.10-2.redhat_1.1.ep7.el6, eap7-jaxen 1.1.6-3.redhat_1.1.ep7.el6, eap7-jsoup 1.8.3-3.redhat_2.1.ep7.el6, eap7-antlr 2.7.7-35.redhat_7.1.ep7.el6, +281 more
    fixed: vendor fix RHSA-2017:3454
  • Red Hat JBoss Enterprise Application Platform 7.1 for RHEL 7 Server eap7-ecj 4.6.1-1.redhat_1.1.ep7.el7, eap7-vdx 1.1.6-1.redhat_1.1.ep7.el7, eap7-xom 1.2.10-2.redhat_1.1.ep7.el7, eap7-jaxen 1.1.6-3.redhat_1.1.ep7.el7, eap7-jsoup 1.8.3-3.redhat_2.1.ep7.el7, eap7-antlr 2.7.7-35.redhat_7.1.ep7.el7, +281 more
    fixed: vendor fix RHSA-2017:3458
  • Red Hat Enterprise Linux 6 tomcat6, tomcat6-lib, tomcat6-log4j, tomcat6-javadoc, tomcat6-webapps, tomcat6-el-2.1-api, +4 more Red Hat Enterprise Linux 7 tomcat, tomcat-lib, tomcat-jsvc, tomcat-javadoc, tomcat-webapps, tomcat-el-2.2-api, +4 more Red Hat JBoss Enterprise Application Platform 6 jbossweb jbossweb Red Hat JBoss Enterprise Web Server 2 tomcat6, tomcat6-lib, tomcat6-log4j, tomcat6-javadoc, tomcat6-webapps, tomcat7 tomcat7, +6 more Red Hat JBoss Enterprise Web Server 3 tomcat7 tomcat7, tomcat8 tomcat8 Red Hat JBoss Operations Network 3 jbossweb jbossweb
    +1 more products
    Red Hat JBoss Portal 6 jbossweb jbossweb
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

2.55% chance of exploitation in the next 30 days, higher than 85% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
NVD 3.0 6.1 CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
NVD 2.0 4.3 AV:N/AC:M/Au:N/C:N/I:P/A:N
GitHub 3.0 6.1 CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Affected packages

ecosystem package affected fixed in
maven org.wildfly:wildfly-undertow
>=10.0.0.Final, <11.0.0.Final
11.0.0.Final

Classification

Weakness
  • CWE-93 Improper Neutralization of CRLF Sequences
  • CWE-113 Improper Neutralization of CRLF Sequences in HTTP Headers

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.