# ELSA-2021-3816: Security update for 11 packages

ELSA-2021-3816, released October 13, 2021, fixes 2 CVEs across 11 products. One of them is being exploited (CVE-2021-40438); 1 on CISA KEV. Patch Radar priority: Patch now.

- Web page: https://patchblox.com/security/fix/linux/elsa-2021-3816
- Platform: Linux
- Released: Oct 13, 2021
- Priority: Patch now (Closes CVE-2021-40438, exploited (CISA KEV, ransomware))
- CVEs: 2, exploited: 1, on CISA KEV: 1
- Vendor advisory: https://linux.oracle.com/errata/ELSA-2021-3816.html

## Applies to

| Product | Release | Fixed in |
|---|---|---|
| [httpd](https://patchblox.com/security/data/product/linux/httpd.md) | ol 8 | 0:2.4.37-39.0.1.module+el8.4.0+20372+b87b2deb.1 |
| [httpd-devel](https://patchblox.com/security/data/product/linux/httpd-devel.md) | ol 8 | 0:2.4.37-39.0.1.module+el8.4.0+20372+b87b2deb.1 |
| [httpd-filesystem](https://patchblox.com/security/data/product/linux/httpd-filesystem.md) | ol 8 | 0:2.4.37-39.0.1.module+el8.4.0+20372+b87b2deb.1 |
| [httpd-manual](https://patchblox.com/security/data/product/linux/httpd-manual.md) | ol 8 | 0:2.4.37-39.0.1.module+el8.4.0+20372+b87b2deb.1 |
| [httpd-tools](https://patchblox.com/security/data/product/linux/httpd-tools.md) | ol 8 | 0:2.4.37-39.0.1.module+el8.4.0+20372+b87b2deb.1 |
| [mod_http2](https://patchblox.com/security/data/product/linux/mod-http2.md) | ol 8 | 0:1.15.7-3.module+el8.4.0+20024+b87b2deb |
| [mod_ldap](https://patchblox.com/security/data/product/linux/mod-ldap.md) | ol 8 | 0:2.4.37-39.0.1.module+el8.4.0+20372+b87b2deb.1 |
| [mod_md](https://patchblox.com/security/data/product/linux/mod-md.md) | ol 8 | 1:2.0.8-8.module+el8.3.0+7816+49791cfd |
| [mod_proxy_html](https://patchblox.com/security/data/product/linux/mod-proxy-html.md) | ol 8 | 1:2.4.37-39.0.1.module+el8.4.0+20372+b87b2deb.1 |
| [mod_session](https://patchblox.com/security/data/product/linux/mod-session.md) | ol 8 | 0:2.4.37-39.0.1.module+el8.4.0+20372+b87b2deb.1 |
| [mod_ssl](https://patchblox.com/security/data/product/linux/mod-ssl.md) | ol 8 | 1:2.4.37-39.0.1.module+el8.4.0+20372+b87b2deb.1 |

## CVEs this fix closes

| CVE | Priority | Title | CVSS | EPSS | Exploitation |
|---|---|---|---:|---:|---|
| [CVE-2021-40438](https://patchblox.com/security/data/cve/CVE-2021-40438.md) | Patch now | httpd: The httpd packages provide the Apache HTTP Server, a powerful, efficient, and extensible web server.  Security Fix(es... | 9.0 | 1.0000 | CISA KEV, Ransomware |
| [CVE-2021-26691](https://patchblox.com/security/data/cve/CVE-2021-26691.md) | High | httpd-tools: The httpd packages provide the Apache HTTP Server, a powerful, efficient, and extensible web server.  Security Fix(es... | 9.8 | 0.6807 |  |

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Data as of 2026-11-07T12:40:37Z 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