Improper input validation in Apache HTTP Server

CVE-2011-4415

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.

Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)

EPSS: 0.031 (86.4th percentile) — read the EPSS interpretation.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2011-4415?
CVE-2011-4415 is a vulnerability in Apache HTTP Server, classified under Improper Input Validation. Published 2011-11-08.
Is CVE-2011-4415 known to be exploited?
24 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.