# CVE-2021-26691: httpd-tools: The httpd packages provide the Apache HTTP Server, a powerful, efficient, and extensible web server.  Security Fix(es...

CVE-2021-26691 is fixed in 19 products on 1 platform, first by apache2 2.4.29-1ubuntu4.16, released June 10, 2021. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2021-26691
- Priority: High
- CVSS: 9.8 (Important)
- EPSS: 0.6807
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Jun 10, 2021

## Description

The httpd packages provide the Apache HTTP Server, a powerful, efficient, and extensible web server.  Security Fix(es):  * httpd: mod_proxy: SSRF via a crafted request uri-path containing "unix:" (CVE-2021-40438)  * httpd: mod_session: Heap overflow via a crafted SessionHeader value (CVE-2021-26691)  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) | 2.4.29-1ubuntu4.16 | [apache2 2.4.29-1ubuntu4.16](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-apache2-2.4.29-1ubuntu4.16.md) | Jun 10, 2021 |
| Linux | apache2 Ubuntu 20.04 LTS (focal) | 2.4.41-4ubuntu3.3 | [apache2 2.4.41-4ubuntu3.3](https://patchblox.com/security/data/fix/linux/ubuntu-focal-apache2-2.4.41-4ubuntu3.3.md) | Jun 10, 2021 |
| Linux | apache2-bin Ubuntu 18.04.6 LTS (bionic) | 2.4.29-1ubuntu4.16 | [apache2-bin 2.4.29-1ubuntu4.16](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-apache2-bin-2.4.29-1ubuntu4.16.md) | Jun 10, 2021 |
| Linux | apache2-bin Ubuntu 20.04 LTS (focal) | 2.4.41-4ubuntu3.3 | [apache2-bin 2.4.41-4ubuntu3.3](https://patchblox.com/security/data/fix/linux/ubuntu-focal-apache2-bin-2.4.41-4ubuntu3.3.md) | Jun 10, 2021 |
| Linux | apache2-data Ubuntu 18.04.6 LTS (bionic) | 2.4.29-1ubuntu4.16 | [apache2-data 2.4.29-1ubuntu4.16](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-apache2-data-2.4.29-1ubuntu4.16.md) | Jun 10, 2021 |
| Linux | apache2-data Ubuntu 20.04 LTS (focal) | 2.4.41-4ubuntu3.3 | [apache2-data 2.4.41-4ubuntu3.3](https://patchblox.com/security/data/fix/linux/ubuntu-focal-apache2-data-2.4.41-4ubuntu3.3.md) | Jun 10, 2021 |
| Linux | apache2-suexec-custom Ubuntu 18.04.6 LTS (bionic) | 2.4.29-1ubuntu4.16 | [apache2-suexec-custom 2.4.29-1ubuntu4.16](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-apache2-suexec-custom-2.4.29-1ubuntu4.16.md) | Jun 10, 2021 |
| Linux | apache2-suexec-custom Ubuntu 20.04 LTS (focal) | 2.4.41-4ubuntu3.3 | [apache2-suexec-custom 2.4.41-4ubuntu3.3](https://patchblox.com/security/data/fix/linux/ubuntu-focal-apache2-suexec-custom-2.4.41-4ubuntu3.3.md) | Jun 10, 2021 |
| Linux | apache2-suexec-pristine Ubuntu 18.04.6 LTS (bionic) | 2.4.29-1ubuntu4.16 | [apache2-suexec-pristine 2.4.29-1ubuntu4.16](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-apache2-suexec-pristine-2.4.29-1ubuntu4.16.md) | Jun 10, 2021 |
| Linux | apache2-suexec-pristine Ubuntu 20.04 LTS (focal) | 2.4.41-4ubuntu3.3 | [apache2-suexec-pristine 2.4.41-4ubuntu3.3](https://patchblox.com/security/data/fix/linux/ubuntu-focal-apache2-suexec-pristine-2.4.41-4ubuntu3.3.md) | Jun 10, 2021 |
| Linux | apache2-utils Ubuntu 18.04.6 LTS (bionic) | 2.4.29-1ubuntu4.16 | [apache2-utils 2.4.29-1ubuntu4.16](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-apache2-utils-2.4.29-1ubuntu4.16.md) | Jun 10, 2021 |
| Linux | apache2-utils Ubuntu 20.04 LTS (focal) | 2.4.41-4ubuntu3.3 | [apache2-utils 2.4.41-4ubuntu3.3](https://patchblox.com/security/data/fix/linux/ubuntu-focal-apache2-utils-2.4.41-4ubuntu3.3.md) | Jun 10, 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 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 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 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 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 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) | 2.4.41-4ubuntu3.3 | [libapache2-mod-md 2.4.41-4ubuntu3.3](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libapache2-mod-md-2.4.41-4ubuntu3.3.md) | Jun 10, 2021 |
| Linux | libapache2-mod-proxy-uwsgi Ubuntu 20.04 LTS (focal) | 2.4.41-4ubuntu3.3 | [libapache2-mod-proxy-uwsgi 2.4.41-4ubuntu3.3](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libapache2-mod-proxy-uwsgi-2.4.41-4ubuntu3.3.md) | Jun 10, 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 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 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 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 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 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 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 |

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