# CVE-2021-33193: httpd: The httpd packages provide the Apache HTTP Server, a powerful, efficient, and extensible web server.  Security Fix(es...

CVE-2021-33193 is fixed in 19 products on 1 platform, first by apache2 2.4.29-1ubuntu4.17, released September 16, 2021. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2021-33193
- Priority: High
- CVSS: 7.5 (Moderate)
- EPSS: 0.4618
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Aug 16, 2021

## Description

The httpd packages provide the Apache HTTP Server, a powerful, efficient, and extensible web server.  Security Fix(es):  * httpd: Request splitting via HTTP/2 method injection and mod_proxy (CVE-2021-33193)  * httpd: mod_proxy_uwsgi: out-of-bounds read via a crafted request uri-path (CVE-2021-36160)  * httpd: possible NULL dereference or SSRF in forward proxy configurations (CVE-2021-44224)  * httpd: Single zero byte stack overflow in mod_auth_digest (CVE-2020-35452)  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 8.6 Release Notes linked from the References section.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | apache2 Ubuntu 18.04.6 LTS (bionic) | 2.4.29-1ubuntu4.17 | [apache2 2.4.29-1ubuntu4.17](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-apache2-2.4.29-1ubuntu4.17.md) | Sep 16, 2021 |
| Linux | apache2 Ubuntu 20.04 LTS (focal) | 2.4.41-4ubuntu3.5 | [apache2 2.4.41-4ubuntu3.5](https://patchblox.com/security/data/fix/linux/ubuntu-focal-apache2-2.4.41-4ubuntu3.5.md) | Sep 16, 2021 |
| Linux | apache2-bin Ubuntu 18.04.6 LTS (bionic) | 2.4.29-1ubuntu4.17 | [apache2-bin 2.4.29-1ubuntu4.17](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-apache2-bin-2.4.29-1ubuntu4.17.md) | Sep 16, 2021 |
| Linux | apache2-bin Ubuntu 20.04 LTS (focal) | 2.4.41-4ubuntu3.5 | [apache2-bin 2.4.41-4ubuntu3.5](https://patchblox.com/security/data/fix/linux/ubuntu-focal-apache2-bin-2.4.41-4ubuntu3.5.md) | Sep 16, 2021 |
| Linux | apache2-data Ubuntu 18.04.6 LTS (bionic) | 2.4.29-1ubuntu4.17 | [apache2-data 2.4.29-1ubuntu4.17](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-apache2-data-2.4.29-1ubuntu4.17.md) | Sep 16, 2021 |
| Linux | apache2-data Ubuntu 20.04 LTS (focal) | 2.4.41-4ubuntu3.5 | [apache2-data 2.4.41-4ubuntu3.5](https://patchblox.com/security/data/fix/linux/ubuntu-focal-apache2-data-2.4.41-4ubuntu3.5.md) | Sep 16, 2021 |
| Linux | apache2-suexec-custom Ubuntu 18.04.6 LTS (bionic) | 2.4.29-1ubuntu4.17 | [apache2-suexec-custom 2.4.29-1ubuntu4.17](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-apache2-suexec-custom-2.4.29-1ubuntu4.17.md) | Sep 16, 2021 |
| Linux | apache2-suexec-custom Ubuntu 20.04 LTS (focal) | 2.4.41-4ubuntu3.5 | [apache2-suexec-custom 2.4.41-4ubuntu3.5](https://patchblox.com/security/data/fix/linux/ubuntu-focal-apache2-suexec-custom-2.4.41-4ubuntu3.5.md) | Sep 16, 2021 |
| Linux | apache2-suexec-pristine Ubuntu 18.04.6 LTS (bionic) | 2.4.29-1ubuntu4.17 | [apache2-suexec-pristine 2.4.29-1ubuntu4.17](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-apache2-suexec-pristine-2.4.29-1ubuntu4.17.md) | Sep 16, 2021 |
| Linux | apache2-suexec-pristine Ubuntu 20.04 LTS (focal) | 2.4.41-4ubuntu3.5 | [apache2-suexec-pristine 2.4.41-4ubuntu3.5](https://patchblox.com/security/data/fix/linux/ubuntu-focal-apache2-suexec-pristine-2.4.41-4ubuntu3.5.md) | Sep 16, 2021 |
| Linux | apache2-utils Ubuntu 18.04.6 LTS (bionic) | 2.4.29-1ubuntu4.17 | [apache2-utils 2.4.29-1ubuntu4.17](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-apache2-utils-2.4.29-1ubuntu4.17.md) | Sep 16, 2021 |
| Linux | apache2-utils Ubuntu 20.04 LTS (focal) | 2.4.41-4ubuntu3.5 | [apache2-utils 2.4.41-4ubuntu3.5](https://patchblox.com/security/data/fix/linux/ubuntu-focal-apache2-utils-2.4.41-4ubuntu3.5.md) | Sep 16, 2021 |
| Linux | httpd RHEL 8 | 0:2.4.37-47.module+el8.6.0+14529+083145da.1 | [RHSA-2022:1915](https://patchblox.com/security/data/fix/linux/rhsa-2022-1915.md) | May 10, 2022 |
| Linux | httpd almalinux 8 | 2.4.37-47.module_el8.6.0+2935+fb177b09.2 | [ALSA-2022:1915](https://patchblox.com/security/data/fix/linux/alsa-2022-1915.md) | May 10, 2022 |
| Linux | httpd ol 8 | 0:2.4.37-43.0.3.module+el8.5.0+20624+5d3b49d0.3 | [ELSA-2022-9276](https://patchblox.com/security/data/fix/linux/elsa-2022-9276.md) | Apr 13, 2022 |
| Linux | httpd rocky 8 | 0:2.4.37-47.module+el8.6.0+823+f143cee1.1 | [RLSA-2022:1915](https://patchblox.com/security/data/fix/linux/rlsa-2022-1915.md) | May 10, 2022 |
| Linux | httpd-devel RHEL 8 | 0:2.4.37-47.module+el8.6.0+14529+083145da.1 | [RHSA-2022:1915](https://patchblox.com/security/data/fix/linux/rhsa-2022-1915.md) | May 10, 2022 |
| Linux | httpd-devel almalinux 8 | 2.4.37-47.module_el8.6.0+2872+fe0ff7aa.1.alma | [ALSA-2022:1915](https://patchblox.com/security/data/fix/linux/alsa-2022-1915.md) | May 10, 2022 |
| Linux | httpd-devel ol 8 | 0:2.4.37-43.0.3.module+el8.5.0+20624+5d3b49d0.3 | [ELSA-2022-9276](https://patchblox.com/security/data/fix/linux/elsa-2022-9276.md) | Apr 13, 2022 |
| Linux | httpd-filesystem RHEL 8 | 0:2.4.37-47.module+el8.6.0+14529+083145da.1 | [RHSA-2022:1915](https://patchblox.com/security/data/fix/linux/rhsa-2022-1915.md) | May 10, 2022 |
| Linux | httpd-filesystem almalinux 8 | 2.4.37-47.module_el8.6.0+2872+fe0ff7aa.1.alma | [ALSA-2022:1915](https://patchblox.com/security/data/fix/linux/alsa-2022-1915.md) | May 10, 2022 |
| Linux | httpd-filesystem ol 8 | 0:2.4.37-43.0.3.module+el8.5.0+20624+5d3b49d0.3 | [ELSA-2022-9276](https://patchblox.com/security/data/fix/linux/elsa-2022-9276.md) | Apr 13, 2022 |
| Linux | httpd-manual RHEL 8 | 0:2.4.37-47.module+el8.6.0+14529+083145da.1 | [RHSA-2022:1915](https://patchblox.com/security/data/fix/linux/rhsa-2022-1915.md) | May 10, 2022 |
| Linux | httpd-manual almalinux 8 | 2.4.37-47.module_el8.6.0+2935+fb177b09.2 | [ALSA-2022:1915](https://patchblox.com/security/data/fix/linux/alsa-2022-1915.md) | May 10, 2022 |
| Linux | httpd-manual ol 8 | 0:2.4.37-43.0.3.module+el8.5.0+20624+5d3b49d0.3 | [ELSA-2022-9276](https://patchblox.com/security/data/fix/linux/elsa-2022-9276.md) | Apr 13, 2022 |
| Linux | httpd-tools RHEL 8 | 0:2.4.37-47.module+el8.6.0+14529+083145da.1 | [RHSA-2022:1915](https://patchblox.com/security/data/fix/linux/rhsa-2022-1915.md) | May 10, 2022 |
| Linux | httpd-tools almalinux 8 | 2.4.37-47.module_el8.6.0+2935+fb177b09.2 | [ALSA-2022:1915](https://patchblox.com/security/data/fix/linux/alsa-2022-1915.md) | May 10, 2022 |
| Linux | httpd-tools ol 8 | 0:2.4.37-43.0.3.module+el8.5.0+20624+5d3b49d0.3 | [ELSA-2022-9276](https://patchblox.com/security/data/fix/linux/elsa-2022-9276.md) | Apr 13, 2022 |
| Linux | libapache2-mod-md Ubuntu 20.04 LTS (focal) | 2.4.41-4ubuntu3.5 | [libapache2-mod-md 2.4.41-4ubuntu3.5](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libapache2-mod-md-2.4.41-4ubuntu3.5.md) | Sep 16, 2021 |
| Linux | libapache2-mod-proxy-uwsgi Ubuntu 20.04 LTS (focal) | 2.4.41-4ubuntu3.5 | [libapache2-mod-proxy-uwsgi 2.4.41-4ubuntu3.5](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libapache2-mod-proxy-uwsgi-2.4.41-4ubuntu3.5.md) | Sep 16, 2021 |
| Linux | mod_http2 RHEL 8 | 0:1.15.7-5.module+el8.6.0+13996+01710940 | [RHSA-2022:1915](https://patchblox.com/security/data/fix/linux/rhsa-2022-1915.md) | May 10, 2022 |
| Linux | mod_http2 almalinux 8 | 1.15.7-5.module_el8.6.0+2872+fe0ff7aa | [ALSA-2022:1915](https://patchblox.com/security/data/fix/linux/alsa-2022-1915.md) | May 10, 2022 |
| Linux | mod_http2 ol 8 | 0:1.15.7-5.module+el8.6.0+20548+01710940 | [ELSA-2022-1915](https://patchblox.com/security/data/fix/linux/elsa-2022-1915.md) | May 17, 2022 |
| Linux | mod_http2 rocky 8 | 0:1.15.7-5.module+el8.6.0+823+f143cee1 | [RLSA-2022:1915](https://patchblox.com/security/data/fix/linux/rlsa-2022-1915.md) | May 10, 2022 |
| Linux | mod_ldap RHEL 8 | 0:2.4.37-47.module+el8.6.0+14529+083145da.1 | [RHSA-2022:1915](https://patchblox.com/security/data/fix/linux/rhsa-2022-1915.md) | May 10, 2022 |
| Linux | mod_ldap almalinux 8 | 2.4.37-47.module_el8.6.0+2935+fb177b09.2 | [ALSA-2022:1915](https://patchblox.com/security/data/fix/linux/alsa-2022-1915.md) | May 10, 2022 |
| Linux | mod_ldap ol 8 | 0:2.4.37-43.0.3.module+el8.5.0+20624+5d3b49d0.3 | [ELSA-2022-9276](https://patchblox.com/security/data/fix/linux/elsa-2022-9276.md) | Apr 13, 2022 |
| Linux | mod_md RHEL 8 | 1:2.0.8-8.module+el8.3.0+6814+67d1e611 | [RHSA-2022:1915](https://patchblox.com/security/data/fix/linux/rhsa-2022-1915.md) | May 10, 2022 |
| Linux | mod_md almalinux 8 | 1:2.0.8-8.module_el8.6.0+2872+fe0ff7aa | [ALSA-2022:1915](https://patchblox.com/security/data/fix/linux/alsa-2022-1915.md) | May 10, 2022 |
| Linux | mod_md ol 8 | 1:2.0.8-8.module+el8.5.0+20475+4f6a8fd5 | [ELSA-2022-1915](https://patchblox.com/security/data/fix/linux/elsa-2022-1915.md) | May 17, 2022 |
| Linux | mod_md rocky 8 | 1:2.0.8-8.module+el8.5.0+695+1fa8055e | [RLSA-2022:1915](https://patchblox.com/security/data/fix/linux/rlsa-2022-1915.md) | May 10, 2022 |
| Linux | mod_proxy_html RHEL 8 | 1:2.4.37-47.module+el8.6.0+14529+083145da.1 | [RHSA-2022:1915](https://patchblox.com/security/data/fix/linux/rhsa-2022-1915.md) | May 10, 2022 |
| Linux | mod_proxy_html almalinux 8 | 1:2.4.37-47.module_el8.6.0+2872+fe0ff7aa.1.alma | [ALSA-2022:1915](https://patchblox.com/security/data/fix/linux/alsa-2022-1915.md) | May 10, 2022 |
| Linux | mod_proxy_html ol 8 | 1:2.4.37-43.0.3.module+el8.5.0+20624+5d3b49d0.3 | [ELSA-2022-9276](https://patchblox.com/security/data/fix/linux/elsa-2022-9276.md) | Apr 13, 2022 |
| Linux | mod_session RHEL 8 | 0:2.4.37-47.module+el8.6.0+14529+083145da.1 | [RHSA-2022:1915](https://patchblox.com/security/data/fix/linux/rhsa-2022-1915.md) | May 10, 2022 |
| Linux | mod_session almalinux 8 | 2.4.37-47.module_el8.6.0+2872+fe0ff7aa.1.alma | [ALSA-2022:1915](https://patchblox.com/security/data/fix/linux/alsa-2022-1915.md) | May 10, 2022 |
| Linux | mod_session ol 8 | 0:2.4.37-43.0.3.module+el8.5.0+20624+5d3b49d0.3 | [ELSA-2022-9276](https://patchblox.com/security/data/fix/linux/elsa-2022-9276.md) | Apr 13, 2022 |
| Linux | mod_ssl RHEL 8 | 1:2.4.37-47.module+el8.6.0+14529+083145da.1 | [RHSA-2022:1915](https://patchblox.com/security/data/fix/linux/rhsa-2022-1915.md) | May 10, 2022 |
| Linux | mod_ssl almalinux 8 | 1:2.4.37-47.module_el8.6.0+2872+fe0ff7aa.1.alma | [ALSA-2022:1915](https://patchblox.com/security/data/fix/linux/alsa-2022-1915.md) | May 10, 2022 |
| Linux | mod_ssl ol 8 | 1:2.4.37-43.0.3.module+el8.5.0+20624+5d3b49d0.3 | [ELSA-2022-9276](https://patchblox.com/security/data/fix/linux/elsa-2022-9276.md) | Apr 13, 2022 |

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