CVE-2021-34798: NULL pointer dereference in httpd core

Published Sep 16, 2021
·
Updated

A NULL pointer dereference in httpd allows an unauthenticated remote attacker to crash httpd by providing malformed HTTP requests. The highest threat from this vulnerability is to system availability.

Other sources

Malformed requests may cause the server to dereference a NULL pointer. This issue affects Apache HTTP Server 2.4.48 and earlier.

Affected Software

45 affected componentsFixes available
redhat/jbcs-httpd24-apr<0:1.6.3-107.el8
0:1.6.3-107.el8
redhat/jbcs-httpd24-apr-util<0:1.6.1-84.el8
0:1.6.1-84.el8
redhat/jbcs-httpd24-curl<0:7.78.0-2.el8
0:7.78.0-2.el8
redhat/jbcs-httpd24-httpd<0:2.4.37-78.el8
0:2.4.37-78.el8
redhat/jbcs-httpd24-nghttp2<0:1.39.2-39.el8
0:1.39.2-39.el8
redhat/jbcs-httpd24-openssl<1:1.1.1g-8.el8
1:1.1.1g-8.el8
redhat/jbcs-httpd24-openssl-chil<0:1.0.0-7.el8
0:1.0.0-7.el8
redhat/jbcs-httpd24-openssl-pkcs11<0:0.4.10-22.el8
0:0.4.10-22.el8
redhat/jbcs-httpd24-apr<0:1.6.3-107.jbcs.el7
0:1.6.3-107.jbcs.el7
redhat/jbcs-httpd24-apr-util<0:1.6.1-84.jbcs.el7
0:1.6.1-84.jbcs.el7
redhat/jbcs-httpd24-curl<0:7.78.0-2.jbcs.el7
0:7.78.0-2.jbcs.el7
redhat/jbcs-httpd24-httpd<0:2.4.37-78.jbcs.el7
0:2.4.37-78.jbcs.el7
redhat/jbcs-httpd24-nghttp2<0:1.39.2-39.jbcs.el7
0:1.39.2-39.jbcs.el7
redhat/jbcs-httpd24-openssl<1:1.1.1g-8.jbcs.el7
1:1.1.1g-8.jbcs.el7
redhat/jbcs-httpd24-openssl-chil<0:1.0.0-7.jbcs.el7
0:1.0.0-7.jbcs.el7
redhat/jbcs-httpd24-openssl-pkcs11<0:0.4.10-22.jbcs.el7
0:0.4.10-22.jbcs.el7
redhat/httpd<0:2.4.6-97.el7_9.4
0:2.4.6-97.el7_9.4
redhat/httpd24-httpd<0:2.4.34-23.el7.5
0:2.4.34-23.el7.5
debian/apache2
2.4.38-3+deb10u82.4.38-3+deb10u102.4.56-1~deb11u22.4.56-1~deb11u12.4.57-22.4.57-32.4.58-1
Apache HTTP Server<=2.4.48
Fedoraproject Fedora=34
Fedoraproject Fedora=35
Debian Debian Linux=9.0
Debian Debian Linux=10.0
Debian Debian Linux=11.0
NetApp Cloud Backup
NetApp Clustered Data ONTAP
NetApp Storagegrid
Tenable Tenable.Sc<=5.19.1
Oracle Communications Cloud Native Core Network Function Cloud Native Environment=1.10.0
Oracle Enterprise Manager Base Platform=13.4.0.0
Oracle Enterprise Manager Base Platform=13.5.0.0
Oracle HTTP Server=12.2.1.3.0
Oracle HTTP Server=12.2.1.4.0
Oracle Instantis Enterprisetrack=17.1
Oracle Instantis Enterprisetrack=17.2
Oracle Instantis Enterprisetrack=17.3
Oracle PeopleSoft Enterprise PeopleTools=8.58
Oracle ZFS Storage Appliance Kit=8.8
Broadcom Brocade Fabric Operating System Firmware
Siemens Ruggedcom Nms
Siemens SINEC NMS
Siemens SINEMA Remote Connect Server<3.1
Siemens SINEMA Server=14.0
redhat/httpd<2.4.49
2.4.49

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade redhat/jbcs-httpd24-apr to a version that resolves this vulnerability.

    Fixed in 0:1.6.3-107.el8
  2. Upgrade

    Upgrade redhat/jbcs-httpd24-apr-util to a version that resolves this vulnerability.

    Fixed in 0:1.6.1-84.el8
  3. Upgrade

    Upgrade redhat/jbcs-httpd24-curl to a version that resolves this vulnerability.

    Fixed in 0:7.78.0-2.el8
  4. Upgrade

    Upgrade redhat/jbcs-httpd24-httpd to a version that resolves this vulnerability.

    Fixed in 0:2.4.37-78.el8
  5. Upgrade

    Upgrade redhat/jbcs-httpd24-nghttp2 to a version that resolves this vulnerability.

    Fixed in 0:1.39.2-39.el8
  6. Upgrade

    Upgrade redhat/jbcs-httpd24-openssl to a version that resolves this vulnerability.

    Fixed in 1:1.1.1g-8.el8
  7. Upgrade

    Upgrade redhat/jbcs-httpd24-openssl-chil to a version that resolves this vulnerability.

    Fixed in 0:1.0.0-7.el8
  8. Upgrade

    Upgrade redhat/jbcs-httpd24-openssl-pkcs11 to a version that resolves this vulnerability.

    Fixed in 0:0.4.10-22.el8
  9. Upgrade

    Upgrade redhat/jbcs-httpd24-apr to a version that resolves this vulnerability.

    Fixed in 0:1.6.3-107.jbcs.el7
  10. Upgrade

    Upgrade redhat/jbcs-httpd24-apr-util to a version that resolves this vulnerability.

    Fixed in 0:1.6.1-84.jbcs.el7
  11. Upgrade

    Upgrade redhat/jbcs-httpd24-curl to a version that resolves this vulnerability.

    Fixed in 0:7.78.0-2.jbcs.el7
  12. Upgrade

    Upgrade redhat/jbcs-httpd24-httpd to a version that resolves this vulnerability.

    Fixed in 0:2.4.37-78.jbcs.el7
  13. Upgrade

    Upgrade redhat/jbcs-httpd24-nghttp2 to a version that resolves this vulnerability.

    Fixed in 0:1.39.2-39.jbcs.el7
  14. Upgrade

    Upgrade redhat/jbcs-httpd24-openssl to a version that resolves this vulnerability.

    Fixed in 1:1.1.1g-8.jbcs.el7
  15. Upgrade

    Upgrade redhat/jbcs-httpd24-openssl-chil to a version that resolves this vulnerability.

    Fixed in 0:1.0.0-7.jbcs.el7
  16. Upgrade

    Upgrade redhat/jbcs-httpd24-openssl-pkcs11 to a version that resolves this vulnerability.

    Fixed in 0:0.4.10-22.jbcs.el7
  17. Upgrade

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

    Fixed in 0:2.4.6-97.el7_9.4
  18. Upgrade

    Upgrade redhat/httpd24-httpd to a version that resolves this vulnerability.

    Fixed in 0:2.4.34-23.el7.5
  19. Upgrade

    Upgrade debian/apache2 to a version that resolves this vulnerability.

    Fixed in 2.4.38-3+deb10u8Fixed in 2.4.38-3+deb10u10Fixed in 2.4.56-1~deb11u2Fixed in 2.4.56-1~deb11u1Fixed in 2.4.57-2Fixed in 2.4.57-3Fixed in 2.4.58-1
  20. Upgrade

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

    Fixed in 2.4.49

Event History

Sep 16, 2021
CVE Published
12:00 AM
CVE Published
via MITRE·02:40 PM
Data Sourced
via MITRE·02:40 PM
DescriptionWeakness
Data Sourced
via Red Hat·08:28 PM
DescriptionSeverityAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

What is CVE-2021-34798?

CVE-2021-34798 is a vulnerability that allows an unauthenticated remote attacker to crash Apache httpd by providing malformed HTTP requests.

2

How does CVE-2021-34798 affect system availability?

CVE-2021-34798 poses a high threat to system availability.

3

What software is affected by CVE-2021-34798?

Apache httpd versions up to and excluding 2.4.49, as well as certain versions of Red Hat httpd and related packages, are affected by CVE-2021-34798.

4

How do I fix CVE-2021-34798?

To fix CVE-2021-34798, upgrade Apache httpd to version 2.4.49 or apply the appropriate patch from Red Hat.

5

Where can I find more information about CVE-2021-34798?

You can find more information about CVE-2021-34798 on the Apache httpd website, Red Hat Bugzilla, and Red Hat support policy page.

Company

Resources

Contact

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