CVE-2021-33195: XSS

Published May 18, 2021
·
Updated

A flaw was found in Go. The LookupCNAME, LookupSRV, LookupMX, LookupNS, and LookupAddr functions in the net package and methods on the Resolver type, may return arbitrary values retrieved from DNS, allowing injection of unexpected contents. The highest threat from this vulnerability is to integrity.

Other sources

Go before 1.15.12 and 1.16.x before 1.16.5 allows injection.

References: https://github.com/golang/go/issues/46241 https://groups.google.com/g/golang-announce/c/RgCMkAEQjSI

— Red Hat

Go before 1.15.13 and 1.16.x before 1.16.5 has functions for DNS lookups that do not validate replies from DNS servers and thus a return value may contain an unsafe injection (e.g. XSS) that does not conform to the RFC1035 format.

— Microsoft

Go before 1.15.13 and 1.16.x before 1.16.5 has functions for DNS lookups that do not validate replies from DNS servers, and thus a return value may contain an unsafe injection (e.g., XSS) that does not conform to the RFC1035 format.

Golang Go could allow a remote attacker to execute arbitrary code on the system, caused by not following RFC 1035 rules in the LookupCNAME, LookupSRV, LookupMX, LookupNS, and LookupAddr functions in net. By sending a specially-crafted request, an attacker could exploit this vulnerability to execute arbitrary code on the system.

— IBM

Affected Software

33 affected componentsFixes available
redhat/openshift-serverless-clients<0:0.23.2-1.el8
0:0.23.2-1.el8
redhat/go-toolset<1.15-golang-0:1.15.14-2.el7_9
1.15-golang-0:1.15.14-2.el7_9
redhat/grafana<0:7.5.9-4.el8
0:7.5.9-4.el8
redhat/buildah<1:1.27.0-2.el9
1:1.27.0-2.el9
redhat/ignition<0:2.6.0-8.rhaos4.6.git947598e.el8
0:2.6.0-8.rhaos4.6.git947598e.el8
redhat/atomic-openshift-service-idler<0:4.7.0-202107291238.p0.git.39cfc66.assembly.stream.el8
0:4.7.0-202107291238.p0.git.39cfc66.assembly.stream.el8
redhat/cri-o<0:1.20.4-7.rhaos4.7.git6287500.el7
0:1.20.4-7.rhaos4.7.git6287500.el7
redhat/ignition<0:2.9.0-4.rhaos4.7.git1d56dc8.el8
0:2.9.0-4.rhaos4.7.git1d56dc8.el8
redhat/openshift<0:4.7.0-202107292242.p0.git.558d959.assembly.stream.el7
0:4.7.0-202107292242.p0.git.558d959.assembly.stream.el7
redhat/openshift-clients<0:4.7.0-202107292242.p0.git.8b4b094.assembly.stream.el8
0:4.7.0-202107292242.p0.git.8b4b094.assembly.stream.el8
redhat/redhat-release-coreos<0:47.84-1.el8
0:47.84-1.el8
redhat/cri-o<0:1.21.2-8.rhaos4.8.git8d4264e.el7
0:1.21.2-8.rhaos4.8.git8d4264e.el7
redhat/ignition<0:2.9.0-7.rhaos4.8.el8
0:2.9.0-7.rhaos4.8.el8
redhat/openshift<0:4.8.0-202107300027.p0.git.38b3ecc.assembly.stream.el7
0:4.8.0-202107300027.p0.git.38b3ecc.assembly.stream.el7
redhat/openshift-clients<0:4.8.0-202107292313.p0.git.1077b05.assembly.stream.el7
0:4.8.0-202107292313.p0.git.1077b05.assembly.stream.el7
redhat/containernetworking-plugins<0:0.8.6-3.rhaos4.6.el7
0:0.8.6-3.rhaos4.6.el7
redhat/cri-tools<0:1.21.0-3.el8
0:1.21.0-3.el8
redhat/golang-github-prometheus-promu<0:0.5.0-4.git642a960.el8
0:0.5.0-4.git642a960.el8
redhat/butane<0:0.12.1-2.rhaos4.8.el8
0:0.12.1-2.rhaos4.8.el8
redhat/mcg<0:5.9.0-28.61dcf87.5.9.el8
0:5.9.0-28.61dcf87.5.9.el8
redhat/etcd<0:3.3.23-3.1.el8
0:3.3.23-3.1.el8
redhat/kubevirt<0:2.6.10-230.el7
0:2.6.10-230.el7
redhat/kubevirt<0:4.8.5-278.el7
0:4.8.5-278.el7
redhat/kubevirt<0:2.6.10-230.el8
0:2.6.10-230.el8
redhat/kubevirt<0:4.8.5-278.el8
0:4.8.5-278.el8
IBM Security Guardium Insights<=3.0
Golang Go<1.15.13
Golang Go>=1.16.0<1.16.5
NetApp Cloud Insights Telegraf Agent
redhat/go<1.16.5
1.16.5
redhat/go<1.15.13
1.15.13
Microsoft azl3 python-tensorboard 2.11.0-3<2.16.2-2
2.16.2-2
Microsoft azl3 python-tensorboard 2.16.2-2<2.16.2-2
2.16.2-2

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

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

    Fixed in 0:0.23.2-1.el8
  2. Upgrade

    Upgrade redhat/go-toolset to a version that resolves this vulnerability.

    Fixed in 1.15-golang-0:1.15.14-2.el7_9
  3. Upgrade

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

    Fixed in 0:7.5.9-4.el8
  4. Upgrade

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

    Fixed in 1:1.27.0-2.el9
  5. Upgrade

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

    Fixed in 0:2.6.0-8.rhaos4.6.git947598e.el8
  6. Upgrade

    Upgrade redhat/atomic-openshift-service-idler to a version that resolves this vulnerability.

    Fixed in 0:4.7.0-202107291238.p0.git.39cfc66.assembly.stream.el8
  7. Upgrade

    Upgrade redhat/cri-o to a version that resolves this vulnerability.

    Fixed in 0:1.20.4-7.rhaos4.7.git6287500.el7
  8. Upgrade

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

    Fixed in 0:2.9.0-4.rhaos4.7.git1d56dc8.el8
  9. Upgrade

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

    Fixed in 0:4.7.0-202107292242.p0.git.558d959.assembly.stream.el7
  10. Upgrade

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

    Fixed in 0:4.7.0-202107292242.p0.git.8b4b094.assembly.stream.el8
  11. Upgrade

    Upgrade redhat/redhat-release-coreos to a version that resolves this vulnerability.

    Fixed in 0:47.84-1.el8
  12. Upgrade

    Upgrade redhat/cri-o to a version that resolves this vulnerability.

    Fixed in 0:1.21.2-8.rhaos4.8.git8d4264e.el7
  13. Upgrade

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

    Fixed in 0:2.9.0-7.rhaos4.8.el8
  14. Upgrade

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

    Fixed in 0:4.8.0-202107300027.p0.git.38b3ecc.assembly.stream.el7
  15. Upgrade

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

    Fixed in 0:4.8.0-202107292313.p0.git.1077b05.assembly.stream.el7
  16. Upgrade

    Upgrade redhat/containernetworking-plugins to a version that resolves this vulnerability.

    Fixed in 0:0.8.6-3.rhaos4.6.el7
  17. Upgrade

    Upgrade redhat/cri-tools to a version that resolves this vulnerability.

    Fixed in 0:1.21.0-3.el8
  18. Upgrade

    Upgrade redhat/golang-github-prometheus-promu to a version that resolves this vulnerability.

    Fixed in 0:0.5.0-4.git642a960.el8
  19. Upgrade

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

    Fixed in 0:0.12.1-2.rhaos4.8.el8
  20. Upgrade

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

    Fixed in 0:5.9.0-28.61dcf87.5.9.el8
  21. Upgrade

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

    Fixed in 0:3.3.23-3.1.el8
  22. Upgrade

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

    Fixed in 0:2.6.10-230.el7
  23. Upgrade

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

    Fixed in 0:4.8.5-278.el7
  24. Upgrade

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

    Fixed in 0:2.6.10-230.el8
  25. Upgrade

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

    Fixed in 0:4.8.5-278.el8
  26. Upgrade

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

    Fixed in 1.16.5
  27. Upgrade

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

    Fixed in 1.15.13
  28. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 2.16.2-2
  29. Upgrade

    Upgrade golang/go to a version that resolves this vulnerability.

    Fixed in 1.15.12
  30. Upgrade

    Upgrade golang/go to a version that resolves this vulnerability.

    Fixed in 1.15.13
  31. Upgrade

    Upgrade golang/go to a version that resolves this vulnerability.

    Fixed in 1.16.5
  32. Compensating control

    As a compensating control, restrict outbound DNS resolution/influence from untrusted networks so an attacker cannot supply specially crafted DNS responses to Go net lookups (LookupCNAME, LookupSRV, LookupMX, LookupNS, LookupAddr) and Resolver methods.

Event History

May 18, 2021
CVE Published
12:00 AM
Aug 2, 2021
CVE Published
via MITRE·06:51 PM
Data Sourced
via MITRE·06:51 PM
Description
Aug 3, 2021
Data Sourced
via Red Hat·01:22 PM
DescriptionSeverityAffected Software
Sep 11, 2024
Data Sourced
via Microsoft·07:00 AM
DescriptionSeverityWeaknessAffected Software
Updated
via Microsoft·07:00 AM
Affected Software
Updated
via Microsoft·07:00 AM
DescriptionSeverity

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

What is CVE-2021-33195?

CVE-2021-33195 is a vulnerability in Go before 1.15.13 and 1.16.x before 1.16.5 that could allow a remote attacker to execute arbitrary code on the system.

2

What is the severity of CVE-2021-33195?

CVE-2021-33195 has a severity rating of 7.5 (High).

3

Which functions in Go are affected by CVE-2021-33195?

The LookupCNAME, LookupSRV, LookupMX, LookupNS, and LookupAddr functions in net are affected by CVE-2021-33195.

4

How can I fix CVE-2021-33195?

You can fix CVE-2021-33195 by updating to Go version 1.15.13 or 1.16.5.

5

Where can I find more information about CVE-2021-33195?

You can find more information about CVE-2021-33195 in the following references: [link1](https://github.com/golang/go/issues/46241), [link2](https://groups.google.com/g/golang-announce/c/RgCMkAEQjSI), [link3](https://bugzilla.redhat.com/show_bug.cgi/show_bug.cgi?id=1989568).

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