RHSA-2021:3816: Important: httpd:2.4 security update

Published Oct 12, 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) httpd: modsession: Heap overflow via a crafted SessionHeader value (CVE-2021-26691) 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<2.4.37-39.module+el8.4.0+12865+a7065a39.1
2.4.37-39.module+el8.4.0+12865+a7065a39.1
redhat/httpd-filesystem<2.4.37-39.module+el8.4.0+12865+a7065a39.1
2.4.37-39.module+el8.4.0+12865+a7065a39.1
redhat/httpd-manual<2.4.37-39.module+el8.4.0+12865+a7065a39.1
2.4.37-39.module+el8.4.0+12865+a7065a39.1
redhat/httpd<2.4.37-39.module+el8.4.0+12865+a7065a39.1
2.4.37-39.module+el8.4.0+12865+a7065a39.1
redhat/httpd-debuginfo<2.4.37-39.module+el8.4.0+12865+a7065a39.1
2.4.37-39.module+el8.4.0+12865+a7065a39.1
redhat/httpd-debugsource<2.4.37-39.module+el8.4.0+12865+a7065a39.1
2.4.37-39.module+el8.4.0+12865+a7065a39.1
redhat/httpd-devel<2.4.37-39.module+el8.4.0+12865+a7065a39.1
2.4.37-39.module+el8.4.0+12865+a7065a39.1
redhat/httpd-tools<2.4.37-39.module+el8.4.0+12865+a7065a39.1
2.4.37-39.module+el8.4.0+12865+a7065a39.1
redhat/httpd-tools-debuginfo<2.4.37-39.module+el8.4.0+12865+a7065a39.1
2.4.37-39.module+el8.4.0+12865+a7065a39.1
redhat/httpd-debuginfo<2.4.37-39.module+el8.4.0+12865+a7065a39.1
2.4.37-39.module+el8.4.0+12865+a7065a39.1
redhat/httpd-debugsource<2.4.37-39.module+el8.4.0+12865+a7065a39.1
2.4.37-39.module+el8.4.0+12865+a7065a39.1
redhat/httpd-devel<2.4.37-39.module+el8.4.0+12865+a7065a39.1
2.4.37-39.module+el8.4.0+12865+a7065a39.1
redhat/httpd-tools<2.4.37-39.module+el8.4.0+12865+a7065a39.1
2.4.37-39.module+el8.4.0+12865+a7065a39.1
redhat/httpd-tools-debuginfo<2.4.37-39.module+el8.4.0+12865+a7065a39.1
2.4.37-39.module+el8.4.0+12865+a7065a39.1
redhat/httpd<2.4.37-39.module+el8.4.0+12865+a7065a39.1
2.4.37-39.module+el8.4.0+12865+a7065a39.1
redhat/httpd-debuginfo<2.4.37-39.module+el8.4.0+12865+a7065a39.1
2.4.37-39.module+el8.4.0+12865+a7065a39.1
redhat/httpd-debugsource<2.4.37-39.module+el8.4.0+12865+a7065a39.1
2.4.37-39.module+el8.4.0+12865+a7065a39.1
redhat/httpd-devel<2.4.37-39.module+el8.4.0+12865+a7065a39.1
2.4.37-39.module+el8.4.0+12865+a7065a39.1
redhat/httpd-tools<2.4.37-39.module+el8.4.0+12865+a7065a39.1
2.4.37-39.module+el8.4.0+12865+a7065a39.1
redhat/httpd-tools-debuginfo<2.4.37-39.module+el8.4.0+12865+a7065a39.1
2.4.37-39.module+el8.4.0+12865+a7065a39.1
redhat/httpd<2.4.37-39.module+el8.4.0+12865+a7065a39.1.aa
2.4.37-39.module+el8.4.0+12865+a7065a39.1.aa
redhat/httpd-debuginfo<2.4.37-39.module+el8.4.0+12865+a7065a39.1.aa
2.4.37-39.module+el8.4.0+12865+a7065a39.1.aa
redhat/httpd-debugsource<2.4.37-39.module+el8.4.0+12865+a7065a39.1.aa
2.4.37-39.module+el8.4.0+12865+a7065a39.1.aa
redhat/httpd-devel<2.4.37-39.module+el8.4.0+12865+a7065a39.1.aa
2.4.37-39.module+el8.4.0+12865+a7065a39.1.aa
redhat/httpd-tools<2.4.37-39.module+el8.4.0+12865+a7065a39.1.aa
2.4.37-39.module+el8.4.0+12865+a7065a39.1.aa
redhat/httpd-tools-debuginfo<2.4.37-39.module+el8.4.0+12865+a7065a39.1.aa
2.4.37-39.module+el8.4.0+12865+a7065a39.1.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 2.4.37-39.module+el8.4.0+12865+a7065a39.1
  2. Upgrade

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

    Fixed in 2.4.37-39.module+el8.4.0+12865+a7065a39.1
  3. Upgrade

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

    Fixed in 2.4.37-39.module+el8.4.0+12865+a7065a39.1
  4. Upgrade

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

    Fixed in 2.4.37-39.module+el8.4.0+12865+a7065a39.1
  5. Upgrade

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

    Fixed in 2.4.37-39.module+el8.4.0+12865+a7065a39.1
  6. Upgrade

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

    Fixed in 2.4.37-39.module+el8.4.0+12865+a7065a39.1
  7. Upgrade

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

    Fixed in 2.4.37-39.module+el8.4.0+12865+a7065a39.1
  8. Upgrade

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

    Fixed in 2.4.37-39.module+el8.4.0+12865+a7065a39.1
  9. Upgrade

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

    Fixed in 2.4.37-39.module+el8.4.0+12865+a7065a39.1.aa
  10. Upgrade

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

    Fixed in 2.4.37-39.module+el8.4.0+12865+a7065a39.1.aa
  11. Upgrade

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

    Fixed in 2.4.37-39.module+el8.4.0+12865+a7065a39.1.aa
  12. Upgrade

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

    Fixed in 2.4.37-39.module+el8.4.0+12865+a7065a39.1.aa
  13. Upgrade

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

    Fixed in 2.4.37-39.module+el8.4.0+12865+a7065a39.1.aa
  14. Upgrade

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

    Fixed in 2.4.37-39.module+el8.4.0+12865+a7065a39.1.aa
  15. Upgrade

    Upgrade httpd to a version that resolves this vulnerability.

    Patch CVE-2021-26691
  16. Upgrade

    Upgrade httpd to a version that resolves this vulnerability.

    Patch CVE-2021-40438

Event History

May 28, 2026
Advisory Published
via Red Hat·04:10 PM
Data Sourced
via Red Hat·04:10 PM
RemedyDescriptionAffected Software
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Frequently Asked Questions

1

What is the severity of RHSA-2021:3816?

The severity of RHSA-2021:3816 is categorized as important.

2

How do I fix RHSA-2021:3816?

To fix RHSA-2021:3816, upgrade the httpd package to version 2.4.37-39.module+el8.4.0+12865+a7065a39.1 or later.

3

What vulnerabilities are addressed in RHSA-2021:3816?

RHSA-2021:3816 addresses SSRF and heap overflow vulnerabilities in the Apache HTTP Server.

4

Which software packages are affected by RHSA-2021:3816?

The affected software packages include httpd, httpd-filesystem, httpd-manual, and several others.

5

Is updating httpd sufficient for RHSA-2021:3816?

Yes, updating the httpd package to the specified version will remediate the vulnerabilities in RHSA-2021:3816.

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