CVE-2021-26690 mod_session NULL pointer dereference
A specially crafted Cookie header in Apache HTTP Server's mod_session module causes a NULL pointer dereference, leading to 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-2021-26690?
CVE-2021-26690 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 2.4.0 to 2.4.46 A specially crafted Cookie header handled by mod_session can cause a NULL pointer dereference and crash, leading to a possible Denial Of Service
Weakness: CWE-476
Which versions are affected by CVE-2021-26690?
1 open source package ship an affected version, including apache. It affects 6 products.
| Package | Affected | Fixed in |
|---|---|---|
apache Bitnami | From 2.4.0 | 2.4.47 |
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-2021-26690?
Upgrade apache to 2.4.47 or later.
Is CVE-2021-26690 being exploited?
There is no known exploitation of CVE-2021-26690 in the wild and no public exploit code.
Public exploit code: 2 proofs of concept on GitHub.
Other vulnerabilities in Apache Http Server
Sources
Also known as ALPINE-CVE-2021-26690, AZL-6476, BIT-apache-2021-26690, CLEANSTART-2026-YR89103, DEBIAN-CVE-2021-26690, GHSA-f669-j28w-pjvg and 2 more.