Memory leak in Apache HTTP Server - CVE-2016-8740
Published: December 5, 2016 / Updated: September 14, 2018
Vulnerability identifier: #VU1209
CSH Severity: Low
CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2016-8740
CWE-ID: CWE-401
Exploitation vector: Remote access
Exploit availability:
Public exploit is available
Vulnerability details
The vulnerability allows a remote attacker to cause denial of service.
The vulnerability exists due to improper handling of HTTP/2 headers, when the Protocols configuration includes h2 or h2c. A remote attacker can send a specially crafted HTTP/2 request, containign CONTINUATION frames to vulnerable instance and consume all available memory resources.
Successful exploitation of the vulnerability will result in denial of service (DoS) of affected web server.
Affected software
Apache HTTP Server
Red Hat Enterprise Linux for x86_64
Slackware Linux
Fedora
httpd
Red Hat Enterprise Linux for x86_64
Slackware Linux
Fedora
httpd
How to mitigate CVE-2016-8740
On December 20 vendor has issued a new version of Apache HTTP Server 2.4.25 to address this vulnerability.
As a temporary solution it is recommended to limit access to HTTP/2 protocol to trusted IPs only.
As a temporary solution it is recommended to limit access to HTTP/2 protocol to trusted IPs only.
httpd - addressed in versions 2.4.23-5.fc23, 2.4.23-5.fc24, 2.4.23-5.fc25