CVE-2021-33197: Input Validation

Published May 21, 2021
·
Updated

A flaw was found in Go, acting as an unintended proxy or intermediary, where ReverseProxy forwards connection headers if the first one was empty. This flaw allows an attacker to drop arbitrary headers. The highest threat from this vulnerability is to integrity.

Other sources

Go before 1.15.12 and 1.16.x before 1.16.5 acts as an Unintended Proxy or Intermediary.

References: https://github.com/golang/go/issues/46313 https://groups.google.com/g/golang-announce/c/RgCMkAEQjSI

— Red Hat

Golang Go could allow a remote attacker to bypass security restrictions, caused by a flaw in the ReverseProxy in net/http/httputil. By sending a specially-crafted request, an attacker could exploit this vulnerability to drop arbitrary headers, including those set by the ReverseProxy.Director.

— IBM

In Go before 1.15.13 and 1.16.x before 1.16.5 some configurations of ReverseProxy (from net/http/httputil) result in a situation where an attacker is able to drop arbitrary headers.

— Microsoft

In Go before 1.15.13 and 1.16.x before 1.16.5, some configurations of ReverseProxy (from net/http/httputil) result in a situation where an attacker is able to drop arbitrary headers.

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/podman<2:4.2.0-3.el9
2:4.2.0-3.el9
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
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/podman to a version that resolves this vulnerability.

    Fixed in 2:4.2.0-3.el9
  5. Upgrade

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

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

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

    Fixed in 0:2.6.0-8.rhaos4.6.git947598e.el8
  7. 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
  8. Upgrade

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

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

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

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

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

    Fixed in 0:4.7.0-202107292242.p0.git.558d959.assembly.stream.el7
  11. 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
  12. Upgrade

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

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

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

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

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

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

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

    Fixed in 0:4.8.0-202107300027.p0.git.38b3ecc.assembly.stream.el7
  16. 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
  17. Upgrade

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

    Fixed in 1.16.5
  28. Upgrade

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

    Fixed in 1.15.13
  29. Upgrade

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

    Fixed in 2.16.2-2
  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

Event History

May 21, 2021
CVE Published
12:00 AM
Aug 2, 2021
CVE Published
via MITRE·06:54 PM
Data Sourced
via MITRE·06:54 PM
Description
Aug 3, 2021
Data Sourced
via Red Hat·01:31 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-2021-33197?

CVE-2021-33197 is a vulnerability in Go that allows a remote attacker to bypass security restrictions.

2

How does CVE-2021-33197 affect Golang Go?

CVE-2021-33197 affects Golang Go versions before 1.15.13 and 1.16.x before 1.16.5.

3

What is the severity of CVE-2021-33197?

CVE-2021-33197 has a severity rating of 7.5 (high).

4

How can an attacker exploit CVE-2021-33197?

An attacker can exploit CVE-2021-33197 by sending a specially-crafted request to drop arbitrary headers.

5

What is the remedy for CVE-2021-33197?

To fix CVE-2021-33197, update your Golang Go installation to version 1.15.13 or 1.16.5.

Company

Resources

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