RHSA-2021:3836: Important: httpd:2.4 security update

Published Oct 13, 2021
·
Updated

The httpd packages provide the Apache HTTP Server, a powerful, efficient, and extensible web server.Security Fix(es): httpd: modproxy: SSRF via a crafted request uri-path containing "unix:" (CVE-2021-40438) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Affected Software

26 affected componentsFixes available
redhat/httpd<2.4.37-21.module+el8.2.0+12904+53ee7aba.1
2.4.37-21.module+el8.2.0+12904+53ee7aba.1
redhat/httpd<2.4.37-21.module+el8.2.0+12904+53ee7aba.1
2.4.37-21.module+el8.2.0+12904+53ee7aba.1
redhat/httpd-debuginfo<2.4.37-21.module+el8.2.0+12904+53ee7aba.1
2.4.37-21.module+el8.2.0+12904+53ee7aba.1
redhat/httpd-debugsource<2.4.37-21.module+el8.2.0+12904+53ee7aba.1
2.4.37-21.module+el8.2.0+12904+53ee7aba.1
redhat/httpd-devel<2.4.37-21.module+el8.2.0+12904+53ee7aba.1
2.4.37-21.module+el8.2.0+12904+53ee7aba.1
redhat/httpd-filesystem<2.4.37-21.module+el8.2.0+12904+53ee7aba.1
2.4.37-21.module+el8.2.0+12904+53ee7aba.1
redhat/httpd-manual<2.4.37-21.module+el8.2.0+12904+53ee7aba.1
2.4.37-21.module+el8.2.0+12904+53ee7aba.1
redhat/httpd-tools<2.4.37-21.module+el8.2.0+12904+53ee7aba.1
2.4.37-21.module+el8.2.0+12904+53ee7aba.1
redhat/httpd-tools-debuginfo<2.4.37-21.module+el8.2.0+12904+53ee7aba.1
2.4.37-21.module+el8.2.0+12904+53ee7aba.1
redhat/httpd-debuginfo<2.4.37-21.module+el8.2.0+12904+53ee7aba.1
2.4.37-21.module+el8.2.0+12904+53ee7aba.1
redhat/httpd-debugsource<2.4.37-21.module+el8.2.0+12904+53ee7aba.1
2.4.37-21.module+el8.2.0+12904+53ee7aba.1
redhat/httpd-devel<2.4.37-21.module+el8.2.0+12904+53ee7aba.1
2.4.37-21.module+el8.2.0+12904+53ee7aba.1
redhat/httpd-tools<2.4.37-21.module+el8.2.0+12904+53ee7aba.1
2.4.37-21.module+el8.2.0+12904+53ee7aba.1
redhat/httpd-tools-debuginfo<2.4.37-21.module+el8.2.0+12904+53ee7aba.1
2.4.37-21.module+el8.2.0+12904+53ee7aba.1
redhat/httpd<2.4.37-21.module+el8.2.0+12904+53ee7aba.1
2.4.37-21.module+el8.2.0+12904+53ee7aba.1
redhat/httpd-debuginfo<2.4.37-21.module+el8.2.0+12904+53ee7aba.1
2.4.37-21.module+el8.2.0+12904+53ee7aba.1
redhat/httpd-debugsource<2.4.37-21.module+el8.2.0+12904+53ee7aba.1
2.4.37-21.module+el8.2.0+12904+53ee7aba.1
redhat/httpd-devel<2.4.37-21.module+el8.2.0+12904+53ee7aba.1
2.4.37-21.module+el8.2.0+12904+53ee7aba.1
redhat/httpd-tools<2.4.37-21.module+el8.2.0+12904+53ee7aba.1
2.4.37-21.module+el8.2.0+12904+53ee7aba.1
redhat/httpd-tools-debuginfo<2.4.37-21.module+el8.2.0+12904+53ee7aba.1
2.4.37-21.module+el8.2.0+12904+53ee7aba.1
redhat/httpd<2.4.37-21.module+el8.2.0+12904+53ee7aba.1.aa
2.4.37-21.module+el8.2.0+12904+53ee7aba.1.aa
redhat/httpd-debuginfo<2.4.37-21.module+el8.2.0+12904+53ee7aba.1.aa
2.4.37-21.module+el8.2.0+12904+53ee7aba.1.aa
redhat/httpd-debugsource<2.4.37-21.module+el8.2.0+12904+53ee7aba.1.aa
2.4.37-21.module+el8.2.0+12904+53ee7aba.1.aa
redhat/httpd-devel<2.4.37-21.module+el8.2.0+12904+53ee7aba.1.aa
2.4.37-21.module+el8.2.0+12904+53ee7aba.1.aa
redhat/httpd-tools<2.4.37-21.module+el8.2.0+12904+53ee7aba.1.aa
2.4.37-21.module+el8.2.0+12904+53ee7aba.1.aa
redhat/httpd-tools-debuginfo<2.4.37-21.module+el8.2.0+12904+53ee7aba.1.aa
2.4.37-21.module+el8.2.0+12904+53ee7aba.1.aa

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

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

    Fixed in 2.4.37-21.module+el8.2.0+12904+53ee7aba.1
  2. Upgrade

    Upgrade redhat/httpd-debuginfo to a version that resolves this vulnerability.

    Fixed in 2.4.37-21.module+el8.2.0+12904+53ee7aba.1
  3. Upgrade

    Upgrade redhat/httpd-debugsource to a version that resolves this vulnerability.

    Fixed in 2.4.37-21.module+el8.2.0+12904+53ee7aba.1
  4. Upgrade

    Upgrade redhat/httpd-devel to a version that resolves this vulnerability.

    Fixed in 2.4.37-21.module+el8.2.0+12904+53ee7aba.1
  5. Upgrade

    Upgrade redhat/httpd-filesystem to a version that resolves this vulnerability.

    Fixed in 2.4.37-21.module+el8.2.0+12904+53ee7aba.1
  6. Upgrade

    Upgrade redhat/httpd-manual to a version that resolves this vulnerability.

    Fixed in 2.4.37-21.module+el8.2.0+12904+53ee7aba.1
  7. Upgrade

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

    Fixed in 2.4.37-21.module+el8.2.0+12904+53ee7aba.1
  8. Upgrade

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

    Fixed in 2.4.37-21.module+el8.2.0+12904+53ee7aba.1
  9. Upgrade

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

    Fixed in 2.4.37-21.module+el8.2.0+12904+53ee7aba.1.aa
  10. Upgrade

    Upgrade redhat/httpd-debuginfo to a version that resolves this vulnerability.

    Fixed in 2.4.37-21.module+el8.2.0+12904+53ee7aba.1.aa
  11. Upgrade

    Upgrade redhat/httpd-debugsource to a version that resolves this vulnerability.

    Fixed in 2.4.37-21.module+el8.2.0+12904+53ee7aba.1.aa
  12. Upgrade

    Upgrade redhat/httpd-devel to a version that resolves this vulnerability.

    Fixed in 2.4.37-21.module+el8.2.0+12904+53ee7aba.1.aa
  13. Upgrade

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

    Fixed in 2.4.37-21.module+el8.2.0+12904+53ee7aba.1.aa
  14. Upgrade

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

    Fixed in 2.4.37-21.module+el8.2.0+12904+53ee7aba.1.aa
  15. Upgrade

    Upgrade httpd to a version that resolves this vulnerability.

    Fixed in 2.4.37-21.module+el8.2.0+12904+53ee7aba.1
  16. Upgrade

    Upgrade mod_http2 to a version that resolves this vulnerability.

    Fixed in 1.11.3-3.module+el8.2.0+7758+84b4ca3e.1
  17. Upgrade

    Upgrade mod_ldap to a version that resolves this vulnerability.

    Fixed in 2.4.37-21.module+el8.2.0+12904+53ee7aba.1
  18. Upgrade

    Upgrade mod_md to a version that resolves this vulnerability.

    Fixed in 2.0.8-7.module+el8.2.0+5531+7e4d69a2
  19. Upgrade

    Upgrade mod_proxy_html to a version that resolves this vulnerability.

    Fixed in 2.4.37-21.module+el8.2.0+12904+53ee7aba.1
  20. Upgrade

    Upgrade mod_session to a version that resolves this vulnerability.

    Fixed in 2.4.37-21.module+el8.2.0+12904+53ee7aba.1
  21. Upgrade

    Upgrade mod_ssl to a version that resolves this vulnerability.

    Fixed in 2.4.37-21.module+el8.2.0+12904+53ee7aba.1

Event History

Jul 26, 2026
Advisory Published
via Red Hat·07:43 PM
Data Sourced
via Red Hat·07:43 PM
RemedyDescriptionAffected Software
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Frequently Asked Questions

1

What is the severity of RHSA-2021:3836?

The severity of RHSA-2021:3836 is classified as important.

2

How do I fix RHSA-2021:3836?

To fix RHSA-2021:3836, update your httpd package to version 2.4.37-21.module+el8.2.0+12904+53ee7aba.1 or later.

3

What does CVE-2021-40438 in RHSA-2021:3836 refer to?

CVE-2021-40438 refers to a Server-Side Request Forgery (SSRF) vulnerability in the mod_proxy module of Apache httpd.

4

Which packages are affected by RHSA-2021:3836?

The affected packages include httpd, httpd-debuginfo, httpd-devel, httpd-tools, and others in the Red Hat Enterprise Linux environment.

5

Is RHSA-2021:3836 related to a specific version of Apache HTTP Server?

Yes, RHSA-2021:3836 is specifically related to Apache HTTP Server version prior to 2.4.37-21.module+el8.2.0+12904+53ee7aba.1.

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