Description
A crafted method sent through HTTP/2 will bypass validation and be forwarded by mod_proxy, which can lead to request splitting or cache poisoning. This issue affects Apache HTTP Server 2.4.17 to 2.4.48.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Apache Software Foundation | Apache HTTP Server | Apache HTTP Server 2.4 2.4.17 to 2.4.48 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | apache2 | 2.4.48-4 | — |
| Debian 13 | apache2 | 2.4.48-4 | — |
| Debian 12 | apache2 | 2.4.48-4 | — |
| Debian 10 | apache2 | 2.4.38-3+deb10u9 | DLA-3351-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | apache2 | 2.4.41-4ubuntu3.5 | USN-5090-1 |
| Ubuntu 18.04 LTS | apache2 | 2.4.29-1ubuntu4.17 | USN-5090-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 8 | httpd +6 | 2.4.37-47.module+el8.6.0+14529+083145da.1 | RHSA-2022:1915 |
| RHEL 8 | mod_http2 | 1.15.7-5.module+el8.6.0+13996+01710940 | RHSA-2022:1915 |
| RHEL 8 | mod_md | 1:2.0.8-8.module+el8.3.0+6814+67d1e611 | RHSA-2022:1915 |
| RHEL 8 | mod_ssl +1 | 1:2.4.37-47.module+el8.6.0+14529+083145da.1 | RHSA-2022:1915 |
| RHEL 3 | httpd24-httpd +5 | 2.4.34-23.el7.5 | RHSA-2022:6753 |
| RHEL 3 | httpd24-mod_ssl +1 | 1:2.4.34-23.el7.5 | RHSA-2022:6753 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Red Hat JBoss Core Services 1 | jbcs-httpd24-httpd +6 | 2.4.51-28.el7jbcs | RHSA-2022:7143 |
| Red Hat JBoss Core Services 1 | jbcs-httpd24-mod_ssl +1 | 1:2.4.51-28.el7jbcs | RHSA-2022:7143 |
AlmaLinux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux 8 | httpd +6 | 2.4.37-47.module_el8.6.0+2872+fe0ff7aa.1.alma | ALSA-2022:1915 |
| AlmaLinux 8 | mod_http2 | 1.15.7-5.module_el8.6.0+2872+fe0ff7aa | ALSA-2022:1915 |
| AlmaLinux 8 | mod_md | 1:2.0.8-8.module_el8.6.0+2872+fe0ff7aa | ALSA-2022:1915 |
| AlmaLinux 8 | mod_ssl +1 | 1:2.4.37-47.module_el8.6.0+2872+fe0ff7aa.1.alma | ALSA-2022:1915 |
Rocky Linux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Rocky Linux 8 | httpd | 2.4.37-47.module+el8.6.0+823+f143cee1.1 | RLSA-2022:1915 |
| Rocky Linux 8 | mod_http2 | 1.15.7-5.module+el8.6.0+823+f143cee1 | RLSA-2022:1915 |
| Rocky Linux 8 | mod_md | 1:2.0.8-8.module+el8.4.0+553+7a69454b | RLSA-2022:1915 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP3 | apache2 | 2.4.43-3.25.1 | SUSE-SU-2021:2954-1 |
| SLES 15 SP2 | apache2 | 2.4.43-3.25.1 | SUSE-SU-2021:2954-1 |
| SLES 15 SP1 | apache2 | 2.4.33-3.55.1 | SUSE-SU-2021:3335-1 |
| SLES 15 | apache2 | 2.4.33-3.55.1 | SUSE-SU-2021:3335-1 |
| SLES 12 SP5 | apache2 | 2.4.23-29.77.2 | SUSE-SU-2021:2918-1 |
Show 6 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 15 SP1 | apache2 | 2.4.33-3.55.1 | SUSE-SU-2021:3335-1 |
| SLES for SAP 15 | apache2 | 2.4.33-3.55.1 | SUSE-SU-2021:3335-1 |
| SLES for SAP 12 SP5 | apache2 | 2.4.23-29.77.2 | SUSE-SU-2021:2918-1 |
| SLE HPC 15 SP1 | apache2 | 2.4.33-3.55.1 | SUSE-SU-2021:3335-1 |
| SLE HPC 15 | apache2 | 2.4.33-3.55.1 | SUSE-SU-2021:3335-1 |
| SUSE Enterprise Storage 6 | apache2 | 2.4.33-3.55.1 | SUSE-SU-2021:3335-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap 15.3 | apache2 | 2.4.43-3.25.1 | openSUSE-SU-2021:2954-1 |
| openSUSE Leap 15.2 | apache2 | 2.4.43-lp152.2.18.1 | openSUSE-SU-2021:1234-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | apache2 | 2.4.49-r0 | — |
| Alpine v3.23 | apache2 | 2.4.49-r0 | — |
| Alpine v3.22 | apache2 | 2.4.49-r0 | — |
| Alpine v3.21 | apache2 | 2.4.49-r0 | — |
| Alpine v3.20 | apache2 | 2.4.49-r0 | — |
Show 9 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.19 | apache2 | 2.4.49-r0 | — |
| Alpine v3.18 | apache2 | 2.4.49-r0 | — |
| Alpine v3.17 | apache2 | 2.4.49-r0 | — |
| Alpine v3.16 | apache2 | 2.4.49-r0 | — |
| Alpine v3.15 | apache2 | 2.4.49-r0 | — |
| Alpine v3.14 | apache2 | 2.4.49-r0 | — |
| Alpine v3.13 | apache2 | 2.4.49-r0 | — |
| Alpine v3.12 | apache2 | 2.4.49-r0 | — |
| Alpine v3.11 | apache2 | 2.4.49-r0 | — |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2 | httpd +7 | 2.4.51-1.amzn2 | ALAS2-2021-1716 |
| Amazon Linux 2 | mod_ssl +1 | 1:2.4.51-1.amzn2 | ALAS2-2021-1716 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 2 (CBL-Mariner) | httpd | 2.4.52-1 | — |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 8 | httpd +6 | 2.4.37-43.0.3.module+el8.5.0+20624+5d3b49d0.3 | ELSA-2022-9276, ELSA-2022-1915 |
| Oracle Linux 8 | mod_http2 | 1.15.7-5.module+el8.6.0+20548+01710940 | ELSA-2022-1915 |
| Oracle Linux 8 | mod_md | 1:2.0.8-8.module+el8.5.0+20475+4f6a8fd5 | ELSA-2022-1915 |
| Oracle Linux 8 | mod_ssl +1 | 1:2.4.37-43.0.3.module+el8.5.0+20624+5d3b49d0.3 | ELSA-2022-9276, ELSA-2022-1915 |
Advisories 17
- ALSA-2022:1915 Moderate: httpd:2.4 security and bug fix update AlmaLinux Security Advisories · Oct 29, 2026
- RHSA-2022:7143 Red Hat Security Advisory: Red Hat JBoss Core Services Apache HTTP Server 2.4.51 security update Red Hat Security Advisories (RHSA) · Oct 9, 2026
- RHSA-2022:6753 Red Hat Security Advisory: httpd24-httpd security and bug fix update Red Hat Security Advisories (RHSA) · Oct 9, 2026
- RHSA-2022:1915 Red Hat Security Advisory: httpd:2.4 security and bug fix update Red Hat Security Advisories (RHSA) · Oct 9, 2026
- USN-5090-1 apache2 vulnerabilities Ubuntu Security Notices (USN) · Apr 22, 2026
- DLA-3351-1 apache2 - security update Debian Security (DSA / DLA) · Mar 9, 2026
- RLSA-2022:1915 Moderate: httpd:2.4 security and bug fix update Rocky Linux Security Advisories · Feb 4, 2026
- openSUSE-SU-2021:1234-1 Security update for apache2 SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2021:3335-1 Security update for apache2 SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2021:2954-1 Security update for apache2 SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2021:2954-1 Security update for apache2 SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2021:2918-1 Security update for apache2 SUSE / openSUSE Security Updates · Feb 4, 2026
- WID-SEC-2024-1591 Juniper JUNOS: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 11, 2024
- WID-SEC-2022-0722 Apache HTTP Server: Schwachstelle ermöglicht Denial of Service BSI CERT-Bund (WID) · Mar 5, 2023
- ELSA-2022-1915 Moderate: httpd:2.4 security and bug fix update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · May 17, 2022
- ELSA-2022-9276 Important: httpd:2.4 security update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · Apr 13, 2022
- ALAS2-2021-1716 Important: httpd security update (Amazon Linux 2) Amazon Linux Security Center (ALAS) · Oct 15, 2021
References
- https://portswigger.net/research/http2
- https://github.com/apache/httpd/commit/ecebcc035ccd8d0e2984fe41420d9e944f456b3c.patch
- [httpd-cvs] 20210916 [httpd-site] branch main updated: Revert "Add descriptions for CVE-2021-33193 CVE-2021-36160" mailing-list
- [httpd-cvs] 20210916 [httpd-site] branch main updated: Add descriptions for CVE-2021-33193 CVE-2021-36160 mailing-list
- FEDORA-2021-5d2d4b6ac5 vendor-advisory
- FEDORA-2021-f94985afca vendor-advisory
- 20211124 Multiple Vulnerabilities in Apache HTTP Server Affecting Cisco Products: November 2021 vendor-advisory
- https://www.oracle.com/security-alerts/cpujan2022.html
- https://security.netapp.com/advisory/ntap-20210917-0004/
- https://www.tenable.com/security/tns-2021-17
- https://www.oracle.com/security-alerts/cpuapr2022.html
- GLSA-202208-20 vendor-advisory
- [debian-lts-announce] 20230303 [SECURITY] [DLA 3351-1] apache2 security update mailing-list