# CVE-2021-40438: httpd: The httpd packages provide the Apache HTTP Server, a powerful, efficient, and extensible web server.  Security Fix(es...

CVE-2021-40438 is fixed in 19 products on 1 platform, first by apache2 2.4.29-1ubuntu4.18, released September 16, 2021. It is being exploited: CISA added it to the Known Exploited Vulnerabilities catalog on December 1, 2021, with known ransomware use. Patch Radar priority: Patch now.

- Web page: https://patchblox.com/security/cve/CVE-2021-40438
- Priority: Patch now
- CVSS: 9.0 (important)
- EPSS: 1.0000
- CISA KEV: listed Dec 1, 2021, federal due date Dec 15, 2021, known ransomware use
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Sep 16, 2021

## Description

The httpd packages provide the Apache HTTP Server, a powerful, efficient, and extensible web server.  Security Fix(es):  * httpd: Regression of CVE-2021-40438 and CVE-2021-26691 fixes in AlmaLinux (CVE-2021-20325)  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.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | apache2 Ubuntu 18.04.6 LTS (bionic) | 2.4.29-1ubuntu4.18 | [apache2 2.4.29-1ubuntu4.18](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-apache2-2.4.29-1ubuntu4.18.md) | Sep 16, 2021 |
| Linux | apache2 Ubuntu 20.04 LTS (focal) | 2.4.41-4ubuntu3.6 | [apache2 2.4.41-4ubuntu3.6](https://patchblox.com/security/data/fix/linux/ubuntu-focal-apache2-2.4.41-4ubuntu3.6.md) | Sep 16, 2021 |
| Linux | apache2-bin Ubuntu 18.04.6 LTS (bionic) | 2.4.29-1ubuntu4.18 | [apache2-bin 2.4.29-1ubuntu4.18](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-apache2-bin-2.4.29-1ubuntu4.18.md) | Sep 16, 2021 |
| Linux | apache2-bin Ubuntu 20.04 LTS (focal) | 2.4.41-4ubuntu3.6 | [apache2-bin 2.4.41-4ubuntu3.6](https://patchblox.com/security/data/fix/linux/ubuntu-focal-apache2-bin-2.4.41-4ubuntu3.6.md) | Sep 16, 2021 |
| Linux | apache2-data Ubuntu 18.04.6 LTS (bionic) | 2.4.29-1ubuntu4.18 | [apache2-data 2.4.29-1ubuntu4.18](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-apache2-data-2.4.29-1ubuntu4.18.md) | Sep 16, 2021 |
| Linux | apache2-data Ubuntu 20.04 LTS (focal) | 2.4.41-4ubuntu3.6 | [apache2-data 2.4.41-4ubuntu3.6](https://patchblox.com/security/data/fix/linux/ubuntu-focal-apache2-data-2.4.41-4ubuntu3.6.md) | Sep 16, 2021 |
| Linux | apache2-suexec-custom Ubuntu 18.04.6 LTS (bionic) | 2.4.29-1ubuntu4.18 | [apache2-suexec-custom 2.4.29-1ubuntu4.18](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-apache2-suexec-custom-2.4.29-1ubuntu4.18.md) | Sep 16, 2021 |
| Linux | apache2-suexec-custom Ubuntu 20.04 LTS (focal) | 2.4.41-4ubuntu3.6 | [apache2-suexec-custom 2.4.41-4ubuntu3.6](https://patchblox.com/security/data/fix/linux/ubuntu-focal-apache2-suexec-custom-2.4.41-4ubuntu3.6.md) | Sep 16, 2021 |
| Linux | apache2-suexec-pristine Ubuntu 18.04.6 LTS (bionic) | 2.4.29-1ubuntu4.18 | [apache2-suexec-pristine 2.4.29-1ubuntu4.18](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-apache2-suexec-pristine-2.4.29-1ubuntu4.18.md) | Sep 16, 2021 |
| Linux | apache2-suexec-pristine Ubuntu 20.04 LTS (focal) | 2.4.41-4ubuntu3.6 | [apache2-suexec-pristine 2.4.41-4ubuntu3.6](https://patchblox.com/security/data/fix/linux/ubuntu-focal-apache2-suexec-pristine-2.4.41-4ubuntu3.6.md) | Sep 16, 2021 |
| Linux | apache2-utils Ubuntu 18.04.6 LTS (bionic) | 2.4.29-1ubuntu4.18 | [apache2-utils 2.4.29-1ubuntu4.18](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-apache2-utils-2.4.29-1ubuntu4.18.md) | Sep 16, 2021 |
| Linux | apache2-utils Ubuntu 20.04 LTS (focal) | 2.4.41-4ubuntu3.6 | [apache2-utils 2.4.41-4ubuntu3.6](https://patchblox.com/security/data/fix/linux/ubuntu-focal-apache2-utils-2.4.41-4ubuntu3.6.md) | Sep 16, 2021 |
| Linux | httpd RHEL 8 | 0:2.4.37-39.module+el8.4.0+12865+a7065a39.1 | [RHSA-2021:3816](https://patchblox.com/security/data/fix/linux/rhsa-2021-3816.md) | Oct 12, 2021 |
| Linux | httpd almalinux 8 | 2.4.37-43.module_el8.5.0+2597+c4b14997.alma | [ALSA-2021:4537](https://patchblox.com/security/data/fix/linux/alsa-2021-4537.md) | Nov 9, 2021 |
| Linux | httpd ol 8 | 0:2.4.37-39.0.1.module+el8.4.0+20372+b87b2deb.1 | [ELSA-2021-3816](https://patchblox.com/security/data/fix/linux/elsa-2021-3816.md) | Oct 13, 2021 |
| Linux | httpd-devel RHEL 8 | 0:2.4.37-39.module+el8.4.0+12865+a7065a39.1 | [RHSA-2021:3816](https://patchblox.com/security/data/fix/linux/rhsa-2021-3816.md) | Oct 12, 2021 |
| Linux | httpd-devel almalinux 8 | 2.4.37-43.module_el8.5.0+2597+c4b14997.alma | [ALSA-2021:4537](https://patchblox.com/security/data/fix/linux/alsa-2021-4537.md) | Nov 9, 2021 |
| Linux | httpd-devel ol 8 | 0:2.4.37-39.0.1.module+el8.4.0+20372+b87b2deb.1 | [ELSA-2021-3816](https://patchblox.com/security/data/fix/linux/elsa-2021-3816.md) | Oct 13, 2021 |
| Linux | httpd-filesystem RHEL 8 | 0:2.4.37-39.module+el8.4.0+12865+a7065a39.1 | [RHSA-2021:3816](https://patchblox.com/security/data/fix/linux/rhsa-2021-3816.md) | Oct 12, 2021 |
| Linux | httpd-filesystem almalinux 8 | 2.4.37-43.module_el8.5.0+2597+c4b14997.alma | [ALSA-2021:4537](https://patchblox.com/security/data/fix/linux/alsa-2021-4537.md) | Nov 9, 2021 |
| Linux | httpd-filesystem ol 8 | 0:2.4.37-39.0.1.module+el8.4.0+20372+b87b2deb.1 | [ELSA-2021-3816](https://patchblox.com/security/data/fix/linux/elsa-2021-3816.md) | Oct 13, 2021 |
| Linux | httpd-manual RHEL 8 | 0:2.4.37-39.module+el8.4.0+12865+a7065a39.1 | [RHSA-2021:3816](https://patchblox.com/security/data/fix/linux/rhsa-2021-3816.md) | Oct 12, 2021 |
| Linux | httpd-manual almalinux 8 | 2.4.37-43.module_el8.5.0+2597+c4b14997.alma | [ALSA-2021:4537](https://patchblox.com/security/data/fix/linux/alsa-2021-4537.md) | Nov 9, 2021 |
| Linux | httpd-manual ol 8 | 0:2.4.37-39.0.1.module+el8.4.0+20372+b87b2deb.1 | [ELSA-2021-3816](https://patchblox.com/security/data/fix/linux/elsa-2021-3816.md) | Oct 13, 2021 |
| Linux | httpd-tools RHEL 8 | 0:2.4.37-39.module+el8.4.0+12865+a7065a39.1 | [RHSA-2021:3816](https://patchblox.com/security/data/fix/linux/rhsa-2021-3816.md) | Oct 12, 2021 |
| Linux | httpd-tools almalinux 8 | 2.4.37-43.module_el8.5.0+2597+c4b14997.alma | [ALSA-2021:4537](https://patchblox.com/security/data/fix/linux/alsa-2021-4537.md) | Nov 9, 2021 |
| Linux | httpd-tools ol 8 | 0:2.4.37-39.0.1.module+el8.4.0+20372+b87b2deb.1 | [ELSA-2021-3816](https://patchblox.com/security/data/fix/linux/elsa-2021-3816.md) | Oct 13, 2021 |
| Linux | libapache2-mod-md Ubuntu 20.04 LTS (focal) | 2.4.41-4ubuntu3.6 | [libapache2-mod-md 2.4.41-4ubuntu3.6](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libapache2-mod-md-2.4.41-4ubuntu3.6.md) | Sep 16, 2021 |
| Linux | libapache2-mod-proxy-uwsgi Ubuntu 20.04 LTS (focal) | 2.4.41-4ubuntu3.6 | [libapache2-mod-proxy-uwsgi 2.4.41-4ubuntu3.6](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libapache2-mod-proxy-uwsgi-2.4.41-4ubuntu3.6.md) | Sep 16, 2021 |
| Linux | mod_http2 RHEL 8 | 0:1.15.7-3.module+el8.4.0+8625+d397f3da | [RHSA-2021:3816](https://patchblox.com/security/data/fix/linux/rhsa-2021-3816.md) | Oct 12, 2021 |
| Linux | mod_http2 almalinux 8 | 1.15.7-3.module_el8.5.0+2609+b30d9eec | [ALBA-2021:4604](https://patchblox.com/security/data/fix/linux/alba-2021-4604.md) | Nov 10, 2021 |
| Linux | mod_http2 ol 8 | 0:1.15.7-3.module+el8.4.0+20024+b87b2deb | [ELSA-2021-3816](https://patchblox.com/security/data/fix/linux/elsa-2021-3816.md) | Oct 13, 2021 |
| Linux | mod_ldap RHEL 8 | 0:2.4.37-39.module+el8.4.0+12865+a7065a39.1 | [RHSA-2021:3816](https://patchblox.com/security/data/fix/linux/rhsa-2021-3816.md) | Oct 12, 2021 |
| Linux | mod_ldap almalinux 8 | 2.4.37-43.module_el8.5.0+2597+c4b14997.alma | [ALSA-2021:4537](https://patchblox.com/security/data/fix/linux/alsa-2021-4537.md) | Nov 9, 2021 |
| Linux | mod_ldap ol 8 | 0:2.4.37-39.0.1.module+el8.4.0+20372+b87b2deb.1 | [ELSA-2021-3816](https://patchblox.com/security/data/fix/linux/elsa-2021-3816.md) | Oct 13, 2021 |
| Linux | mod_md RHEL 8 | 1:2.0.8-8.module+el8.3.0+6814+67d1e611 | [RHSA-2021:3816](https://patchblox.com/security/data/fix/linux/rhsa-2021-3816.md) | Oct 12, 2021 |
| Linux | mod_md almalinux 8 | 1:2.0.8-8.module_el8.5.0+2609+b30d9eec | [ALBA-2021:4604](https://patchblox.com/security/data/fix/linux/alba-2021-4604.md) | Nov 10, 2021 |
| Linux | mod_md ol 8 | 1:2.0.8-8.module+el8.3.0+7816+49791cfd | [ELSA-2021-3816](https://patchblox.com/security/data/fix/linux/elsa-2021-3816.md) | Oct 13, 2021 |
| Linux | mod_proxy_html RHEL 8 | 1:2.4.37-39.module+el8.4.0+12865+a7065a39.1 | [RHSA-2021:3816](https://patchblox.com/security/data/fix/linux/rhsa-2021-3816.md) | Oct 12, 2021 |
| Linux | mod_proxy_html almalinux 8 | 1:2.4.37-43.module_el8.5.0+2597+c4b14997.alma | [ALSA-2021:4537](https://patchblox.com/security/data/fix/linux/alsa-2021-4537.md) | Nov 9, 2021 |
| Linux | mod_proxy_html ol 8 | 1:2.4.37-39.0.1.module+el8.4.0+20372+b87b2deb.1 | [ELSA-2021-3816](https://patchblox.com/security/data/fix/linux/elsa-2021-3816.md) | Oct 13, 2021 |
| Linux | mod_session RHEL 8 | 0:2.4.37-39.module+el8.4.0+12865+a7065a39.1 | [RHSA-2021:3816](https://patchblox.com/security/data/fix/linux/rhsa-2021-3816.md) | Oct 12, 2021 |
| Linux | mod_session almalinux 8 | 2.4.37-43.module_el8.5.0+2597+c4b14997.alma | [ALSA-2021:4537](https://patchblox.com/security/data/fix/linux/alsa-2021-4537.md) | Nov 9, 2021 |
| Linux | mod_session ol 8 | 0:2.4.37-39.0.1.module+el8.4.0+20372+b87b2deb.1 | [ELSA-2021-3816](https://patchblox.com/security/data/fix/linux/elsa-2021-3816.md) | Oct 13, 2021 |
| Linux | mod_ssl RHEL 8 | 1:2.4.37-39.module+el8.4.0+12865+a7065a39.1 | [RHSA-2021:3816](https://patchblox.com/security/data/fix/linux/rhsa-2021-3816.md) | Oct 12, 2021 |
| Linux | mod_ssl almalinux 8 | 1:2.4.37-43.module_el8.5.0+2597+c4b14997.alma | [ALSA-2021:4537](https://patchblox.com/security/data/fix/linux/alsa-2021-4537.md) | Nov 9, 2021 |
| Linux | mod_ssl ol 8 | 1:2.4.37-39.0.1.module+el8.4.0+20372+b87b2deb.1 | [ELSA-2021-3816](https://patchblox.com/security/data/fix/linux/elsa-2021-3816.md) | Oct 13, 2021 |

---

Data as of 2026-11-08T06:59:42Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

Free to use with attribution: show "Data: Patchblox Patch Radar" with a link to https://patchblox.com/security/patch-radar. Terms, including what needs a written agreement: https://patchblox.com/security/patch-radar/use-the-data

Product names, logos and trademarks shown on Patch Radar belong to their respective owners. They are used only to identify the software each security fix applies to and to help readers find their platform. Their use does not imply any affiliation with, or endorsement by, those owners, and Patchblox is not affiliated with any of them.