CVE-2020-13950 mod_proxy_http NULL pointer dereference
Attackers can crash Apache HTTP Server by sending crafted requests with conflicting headers, causing a denial of service.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2020-13950?
CVE-2020-13950 is a high-severity vulnerability in Apache Http Server, published on 10 Jun 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Apache HTTP Server versions 2.4.41 to 2.4.46 mod_proxy_http can be made to crash (NULL pointer dereference) with specially crafted requests using both Content-Length and Transfer-Encoding headers, leading to a Denial of Service
Weakness: CWE-476
Which versions are affected by CVE-2020-13950?
1 open source package ship an affected version, including apache. It affects 6 products.
| Package | Affected | Fixed in |
|---|---|---|
apache Bitnami | From 2.4.41 | 2.4.47 |
Linux distribution packages (26)
httpd Red Hat:enterprise_linux:8::appstream | All versions | 0:2.4.37-47.module+el8.6.0+15654+427eba2e.2 |
httpd-debuginfo Red Hat:enterprise_linux:8::appstream | All versions | 0:2.4.37-47.module+el8.6.0+15654+427eba2e.2 |
httpd-debugsource Red Hat:enterprise_linux:8::appstream | All versions | 0:2.4.37-47.module+el8.6.0+15654+427eba2e.2 |
httpd-devel Red Hat:enterprise_linux:8::appstream | All versions | 0:2.4.37-47.module+el8.6.0+15654+427eba2e.2 |
httpd-filesystem Red Hat:enterprise_linux:8::appstream | All versions | 0:2.4.37-47.module+el8.6.0+15654+427eba2e.2 |
httpd-manual Red Hat:enterprise_linux:8::appstream | All versions | 0:2.4.37-47.module+el8.6.0+15654+427eba2e.2 |
httpd-tools Red Hat:enterprise_linux:8::appstream | All versions | 0:2.4.37-47.module+el8.6.0+15654+427eba2e.2 |
httpd-tools-debuginfo Red Hat:enterprise_linux:8::appstream | All versions | 0:2.4.37-47.module+el8.6.0+15654+427eba2e.2 |
mod_http2 Red Hat:enterprise_linux:8::appstream | All versions | 0:1.15.7-5.module+el8.6.0+13996+01710940 |
mod_http2-debuginfo Red Hat:enterprise_linux:8::appstream | All versions | 0:1.15.7-5.module+el8.6.0+13996+01710940 |
mod_http2-debugsource Red Hat:enterprise_linux:8::appstream | All versions | 0:1.15.7-5.module+el8.6.0+13996+01710940 |
mod_ldap Red Hat:enterprise_linux:8::appstream | All versions | 0:2.4.37-47.module+el8.6.0+15654+427eba2e.2 |
mod_ldap-debuginfo Red Hat:enterprise_linux:8::appstream | All versions | 0:2.4.37-47.module+el8.6.0+15654+427eba2e.2 |
mod_md Red Hat:enterprise_linux:8::appstream | All versions | 1:2.0.8-8.module+el8.3.0+6814+67d1e611 |
mod_md-debuginfo Red Hat:enterprise_linux:8::appstream | All versions | 1:2.0.8-8.module+el8.3.0+6814+67d1e611 |
mod_md-debugsource Red Hat:enterprise_linux:8::appstream | All versions | 1:2.0.8-8.module+el8.3.0+6814+67d1e611 |
mod_proxy_html Red Hat:enterprise_linux:8::appstream | All versions | 1:2.4.37-47.module+el8.6.0+15654+427eba2e.2 |
mod_proxy_html-debuginfo Red Hat:enterprise_linux:8::appstream | All versions | 1:2.4.37-47.module+el8.6.0+15654+427eba2e.2 |
mod_session Red Hat:enterprise_linux:8::appstream | All versions | 0:2.4.37-47.module+el8.6.0+15654+427eba2e.2 |
mod_session-debuginfo Red Hat:enterprise_linux:8::appstream | All versions | 0:2.4.37-47.module+el8.6.0+15654+427eba2e.2 |
mod_ssl Red Hat:enterprise_linux:8::appstream | All versions | 1:2.4.37-47.module+el8.6.0+15654+427eba2e.2 |
mod_ssl-debuginfo Red Hat:enterprise_linux:8::appstream | All versions | 1:2.4.37-47.module+el8.6.0+15654+427eba2e.2 |
httpd Rocky Linux:8 | All versions | 0:2.4.37-47.module+el8.6.0+823+f143cee1.1 |
mod_http2 Rocky Linux:8 | All versions | 0:1.15.7-5.module+el8.6.0+823+f143cee1 |
mod_md Rocky Linux:8 | All versions | 1:2.0.8-8.module+el8.4.0+553+7a69454b |
mod_md Rocky Linux:8 | All versions | 1:2.0.8-8.module+el8.5.0+695+1fa8055e |
Products include Apache Http Server, Debian Debian Linux, Fedoraproject Fedora, Oracle Enterprise Manager Ops Center, Oracle Instantis Enterprisetrack, Oracle Zfs Storage Appliance Kit.
How do I fix CVE-2020-13950?
Upgrade apache to 2.4.47 or later.
Is CVE-2020-13950 being exploited?
There is no known exploitation of CVE-2020-13950 in the wild and no public exploit code.
Other vulnerabilities in Apache Http Server
Sources
Also known as ALPINE-CVE-2020-13950, AZL-6474, BIT-apache-2020-13950, CLEANSTART-2026-KT91017, DEBIAN-CVE-2020-13950, GHSA-pqc6-p826-c5qw and 3 more.