CVE-2011-4415 Denial of service in n/a

What is CVE-2011-4415?

CVE-2011-4415 is a low-severity denial of service vulnerability in Apache Http Server, published on 8 Nov 2011. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

The ap_pregsub function in server/util.c in the Apache HTTP Server 2.0.x through 2.0.64 and 2.2.x through 2.2.21, when the mod_setenvif module is enabled, does not restrict the size of values of environment variables, which allows local users to cause a denial of service (memory consumption or NULL pointer dereference) via a .htaccess file with a crafted SetEnvIf directive, in conjunction with a crafted HTTP request header, related to (1) the "len +=" statement and (2) the apr_pcalloc function call, a different vulnerability than CVE-2011-3607.

Weakness: CWE-20

Which versions are affected by CVE-2011-4415?

It affects 1 product.

Products include Apache Http Server.

How do I fix CVE-2011-4415?

Upgrade to a fixed version.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2011-4415 being exploited?

There is no known exploitation of CVE-2011-4415 in the wild and no public exploit code.

Public exploit code: 1 Exploit-DB entry.

Other vulnerabilities in Apache Http Server

• CVE-2021-42013 Apache HTTP Server Path Traversal Exploited Critical 9.8
• CVE-2024-38475 Apache HTTP Server Improper Escaping of Output Exploited Critical 9.1
• CVE-2021-40438 Apache HTTP Server-Side Request Forgery (SSRF) Exploited Critical 9.0
• CVE-2019-0211 Apache HTTP Server Privilege Escalation Exploited High 7.8
• CVE-2021-41773 Apache HTTP Server Path Traversal Exploited High 7.5

All Apache Http Server vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as DEBIAN-CVE-2011-4415, GHSA-43r8-mvrp-6q9c.