RHSA-2021:4257: Moderate: httpd:2.4 security, bug fix, and enhancement update

Published Nov 9, 2021
·
Updated

The httpd packages provide the Apache HTTP Server, a powerful, efficient, and extensible web server.Security Fix(es): httpd: modsession: NULL pointer dereference when parsing Cookie header (CVE-2021-26690) httpd: Unexpected URL matching with 'MergeSlashes OFF' (CVE-2021-30641) 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.Additional Changes:For detailed information on changes in this release, see the Red Hat Enterprise Linux 8.5 Release Notes linked from the References section.

Affected Software

26 affected componentsFixes available
redhat/httpd<2.4.37-41.module+el8.5.0+11772+c8e0c271
2.4.37-41.module+el8.5.0+11772+c8e0c271
redhat/httpd-filesystem<2.4.37-41.module+el8.5.0+11772+c8e0c271
2.4.37-41.module+el8.5.0+11772+c8e0c271
redhat/httpd-manual<2.4.37-41.module+el8.5.0+11772+c8e0c271
2.4.37-41.module+el8.5.0+11772+c8e0c271
redhat/httpd<2.4.37-41.module+el8.5.0+11772+c8e0c271
2.4.37-41.module+el8.5.0+11772+c8e0c271
redhat/httpd-debuginfo<2.4.37-41.module+el8.5.0+11772+c8e0c271
2.4.37-41.module+el8.5.0+11772+c8e0c271
redhat/httpd-debugsource<2.4.37-41.module+el8.5.0+11772+c8e0c271
2.4.37-41.module+el8.5.0+11772+c8e0c271
redhat/httpd-devel<2.4.37-41.module+el8.5.0+11772+c8e0c271
2.4.37-41.module+el8.5.0+11772+c8e0c271
redhat/httpd-tools<2.4.37-41.module+el8.5.0+11772+c8e0c271
2.4.37-41.module+el8.5.0+11772+c8e0c271
redhat/httpd-tools-debuginfo<2.4.37-41.module+el8.5.0+11772+c8e0c271
2.4.37-41.module+el8.5.0+11772+c8e0c271
redhat/httpd-debuginfo<2.4.37-41.module+el8.5.0+11772+c8e0c271
2.4.37-41.module+el8.5.0+11772+c8e0c271
redhat/httpd-debugsource<2.4.37-41.module+el8.5.0+11772+c8e0c271
2.4.37-41.module+el8.5.0+11772+c8e0c271
redhat/httpd-devel<2.4.37-41.module+el8.5.0+11772+c8e0c271
2.4.37-41.module+el8.5.0+11772+c8e0c271
redhat/httpd-tools<2.4.37-41.module+el8.5.0+11772+c8e0c271
2.4.37-41.module+el8.5.0+11772+c8e0c271
redhat/httpd-tools-debuginfo<2.4.37-41.module+el8.5.0+11772+c8e0c271
2.4.37-41.module+el8.5.0+11772+c8e0c271
redhat/httpd<2.4.37-41.module+el8.5.0+11772+c8e0c271
2.4.37-41.module+el8.5.0+11772+c8e0c271
redhat/httpd-debuginfo<2.4.37-41.module+el8.5.0+11772+c8e0c271
2.4.37-41.module+el8.5.0+11772+c8e0c271
redhat/httpd-debugsource<2.4.37-41.module+el8.5.0+11772+c8e0c271
2.4.37-41.module+el8.5.0+11772+c8e0c271
redhat/httpd-devel<2.4.37-41.module+el8.5.0+11772+c8e0c271
2.4.37-41.module+el8.5.0+11772+c8e0c271
redhat/httpd-tools<2.4.37-41.module+el8.5.0+11772+c8e0c271
2.4.37-41.module+el8.5.0+11772+c8e0c271
redhat/httpd-tools-debuginfo<2.4.37-41.module+el8.5.0+11772+c8e0c271
2.4.37-41.module+el8.5.0+11772+c8e0c271
redhat/httpd<2.4.37-41.module+el8.5.0+11772+c8e0c271.aa
2.4.37-41.module+el8.5.0+11772+c8e0c271.aa
redhat/httpd-debuginfo<2.4.37-41.module+el8.5.0+11772+c8e0c271.aa
2.4.37-41.module+el8.5.0+11772+c8e0c271.aa
redhat/httpd-debugsource<2.4.37-41.module+el8.5.0+11772+c8e0c271.aa
2.4.37-41.module+el8.5.0+11772+c8e0c271.aa
redhat/httpd-devel<2.4.37-41.module+el8.5.0+11772+c8e0c271.aa
2.4.37-41.module+el8.5.0+11772+c8e0c271.aa
redhat/httpd-tools<2.4.37-41.module+el8.5.0+11772+c8e0c271.aa
2.4.37-41.module+el8.5.0+11772+c8e0c271.aa
redhat/httpd-tools-debuginfo<2.4.37-41.module+el8.5.0+11772+c8e0c271.aa
2.4.37-41.module+el8.5.0+11772+c8e0c271.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 2.4.37-41.module+el8.5.0+11772+c8e0c271
  2. Upgrade

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

    Fixed in 2.4.37-41.module+el8.5.0+11772+c8e0c271
  3. Upgrade

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

    Fixed in 2.4.37-41.module+el8.5.0+11772+c8e0c271
  4. Upgrade

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

    Fixed in 2.4.37-41.module+el8.5.0+11772+c8e0c271
  5. Upgrade

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

    Fixed in 2.4.37-41.module+el8.5.0+11772+c8e0c271
  6. Upgrade

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

    Fixed in 2.4.37-41.module+el8.5.0+11772+c8e0c271
  7. Upgrade

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

    Fixed in 2.4.37-41.module+el8.5.0+11772+c8e0c271
  8. Upgrade

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

    Fixed in 2.4.37-41.module+el8.5.0+11772+c8e0c271
  9. Upgrade

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

    Fixed in 2.4.37-41.module+el8.5.0+11772+c8e0c271.aa
  10. Upgrade

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

    Fixed in 2.4.37-41.module+el8.5.0+11772+c8e0c271.aa
  11. Upgrade

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

    Fixed in 2.4.37-41.module+el8.5.0+11772+c8e0c271.aa
  12. Upgrade

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

    Fixed in 2.4.37-41.module+el8.5.0+11772+c8e0c271.aa
  13. Upgrade

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

    Fixed in 2.4.37-41.module+el8.5.0+11772+c8e0c271.aa
  14. Upgrade

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

    Fixed in 2.4.37-41.module+el8.5.0+11772+c8e0c271.aa
  15. Upgrade

    Upgrade httpd:2.4 (RPM module package) to a version that resolves this vulnerability.

    Fixed in httpd-2.4.37-41.module+el8.5.0+11772+c8e0c271
  16. Upgrade

    Upgrade mod_http2 (RPM module package) to a version that resolves this vulnerability.

    Fixed in mod_http2-1.15.7-3.module+el8.4.0+8625+d397f3da
  17. Upgrade

    Upgrade mod_ldap (RPM module package) to a version that resolves this vulnerability.

    Fixed in mod_ldap-2.4.37-41.module+el8.5.0+11772+c8e0c271
  18. Upgrade

    Upgrade mod_md (RPM module package) to a version that resolves this vulnerability.

    Fixed in mod_md-2.0.8-8.module+el8.3.0+6814+67d1e611
  19. Upgrade

    Upgrade mod_proxy_html (RPM module package) to a version that resolves this vulnerability.

    Fixed in mod_proxy_html-2.4.37-41.module+el8.5.0+11772+c8e0c271
  20. Upgrade

    Upgrade mod_session (RPM module package) to a version that resolves this vulnerability.

    Fixed in mod_session-2.4.37-41.module+el8.5.0+11772+c8e0c271
  21. Upgrade

    Upgrade mod_ssl (RPM module package) to a version that resolves this vulnerability.

    Fixed in mod_ssl-2.4.37-41.module+el8.5.0+11772+c8e0c271

Event History

Jul 27, 2026
Advisory Published
via Red Hat·05:31 PM
Data Sourced
via Red Hat·05:31 PM
RemedyDescriptionAffected Software
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Frequently Asked Questions

1

What is the severity of RHSA-2021:4257?

The severity of RHSA-2021:4257 is classified as moderate.

2

How do I fix RHSA-2021:4257?

To fix RHSA-2021:4257, update the httpd package to version 2.4.37-41.module+el8.5.0+11772+c8e0c271.

3

What vulnerabilities are addressed in RHSA-2021:4257?

RHSA-2021:4257 addresses vulnerabilities including a NULL pointer dereference in mod_session and unexpected URL matching when 'MergeSlashes' is set to OFF.

4

Which versions of httpd are affected by RHSA-2021:4257?

Versions of httpd before 2.4.37-41.module+el8.5.0+11772+c8e0c271 are affected by RHSA-2021:4257.

5

What software packages are related to RHSA-2021:4257?

RHSA-2021:4257 relates to the httpd, httpd-debuginfo, httpd-devel, and related packages.

Company

Resources

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