CVE-2021-21603: XSS

Published Jan 13, 2021
·
Updated

A flaw was found in jenkins. A cross-site scripting (XSS) vulnerability is possible due to the contents of the notification bar responses not being properly escaped. The highest threat from this vulnerability is to data confidentiality and integrity.

Other sources

Jenkins 2.274 and earlier, LTS 2.263.1 and earlier does not escape notification bar response contents (typically shown after form submissions via Apply button).

This results in a cross-site scripting (XSS) vulnerability exploitable by attackers able to influence notification bar contents.

Jenkins 2.275, LTS 2.263.2 escapes the content shown in notification bars.

Jenkins 2.274 and earlier, LTS 2.263.1 and earlier does not escape notification bar response contents, resulting in a cross-site scripting (XSS) vulnerability.

Affected Software

15 affected componentsFixes available
redhat/jenkins<0:2.263.3.1612433584-1.el7
0:2.263.3.1612433584-1.el7
redhat/conmon<2:2.0.21-1.rhaos4.5.el7
2:2.0.21-1.rhaos4.5.el7
redhat/jenkins<0:2.263.3.1612434332-1.el7
0:2.263.3.1612434332-1.el7
redhat/machine-config-daemon<0:4.5.0-202102050524.p0.git.2594.ff3b8c0.el8
0:4.5.0-202102050524.p0.git.2594.ff3b8c0.el8
redhat/openshift<0:4.5.0-202102050524.p0.git.0.9229406.el7
0:4.5.0-202102050524.p0.git.0.9229406.el7
redhat/openshift-ansible<0:4.5.0-202102031005.p0.git.0.c6839a2.el7
0:4.5.0-202102031005.p0.git.0.c6839a2.el7
redhat/openshift-clients<0:4.5.0-202102051529.p0.git.3612.61b096a.el8
0:4.5.0-202102051529.p0.git.3612.61b096a.el8
redhat/runc<0:1.0.0-72.rhaos4.5.giteadfc6b.el8
0:1.0.0-72.rhaos4.5.giteadfc6b.el8
redhat/jenkins<0:2.263.3.1612434510-1.el8
0:2.263.3.1612434510-1.el8
maven/org.jenkins-ci.main:jenkins-core>=2.263.2<=2.274
2.275
maven/org.jenkins-ci.main:jenkins-core<2.263.1
2.275
redhat/jenkins<2.275
2.275
redhat/jenkins LTS<2.263.2
2.263.2
Jenkins Jenkins<=2.263.1
Jenkins Jenkins<=2.274

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade redhat/jenkins to a version that resolves this vulnerability.

    Fixed in 0:2.263.3.1612433584-1.el7
  2. Upgrade

    Upgrade redhat/conmon to a version that resolves this vulnerability.

    Fixed in 2:2.0.21-1.rhaos4.5.el7
  3. Upgrade

    Upgrade redhat/jenkins to a version that resolves this vulnerability.

    Fixed in 0:2.263.3.1612434332-1.el7
  4. Upgrade

    Upgrade redhat/machine-config-daemon to a version that resolves this vulnerability.

    Fixed in 0:4.5.0-202102050524.p0.git.2594.ff3b8c0.el8
  5. Upgrade

    Upgrade redhat/openshift to a version that resolves this vulnerability.

    Fixed in 0:4.5.0-202102050524.p0.git.0.9229406.el7
  6. Upgrade

    Upgrade redhat/openshift-ansible to a version that resolves this vulnerability.

    Fixed in 0:4.5.0-202102031005.p0.git.0.c6839a2.el7
  7. Upgrade

    Upgrade redhat/openshift-clients to a version that resolves this vulnerability.

    Fixed in 0:4.5.0-202102051529.p0.git.3612.61b096a.el8
  8. Upgrade

    Upgrade redhat/runc to a version that resolves this vulnerability.

    Fixed in 0:1.0.0-72.rhaos4.5.giteadfc6b.el8
  9. Upgrade

    Upgrade redhat/jenkins to a version that resolves this vulnerability.

    Fixed in 0:2.263.3.1612434510-1.el8
  10. Upgrade

    Upgrade maven/org.jenkins-ci.main:jenkins-core to a version that resolves this vulnerability.

    Fixed in 2.275
  11. Upgrade

    Upgrade redhat/jenkins to a version that resolves this vulnerability.

    Fixed in 2.275
  12. Upgrade

    Upgrade redhat/jenkins LTS to a version that resolves this vulnerability.

    Fixed in 2.263.2

Event History

Jan 13, 2021
CVE Published
12:00 AM
CVE Published
via MITRE·03:55 PM
Data Sourced
via MITRE·03:55 PM
Description
Feb 4, 2021
Data Sourced
via Red Hat·02:00 PM
DescriptionSeverityAffected Software
May 24, 2022
Advisory Published
05:39 PM

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

What is the severity of CVE-2021-21603?

The severity of CVE-2021-21603 is high due to its potential impact on data confidentiality and integrity.

2

How do I fix CVE-2021-21603?

To fix CVE-2021-21603, upgrade Jenkins to version 2.275 or later.

3

Which versions of Jenkins are affected by CVE-2021-21603?

Jenkins versions 2.274 and earlier, including LTS 2.263.1 and earlier, are affected by CVE-2021-21603.

4

What type of vulnerability is CVE-2021-21603?

CVE-2021-21603 is a cross-site scripting (XSS) vulnerability.

5

Can CVE-2021-21603 lead to data breaches?

Yes, CVE-2021-21603 can potentially lead to data breaches by compromising data confidentiality and integrity.

Company

Resources

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