CVE-2021-31618

Updated: 2024-11-30 02:06:43.079123

Description:

Apache HTTP Server protocol handler for the HTTP/2 protocol checks received request headers against the size limitations as configured for the server and used for the HTTP/1 protocol as well. On violation of these restrictions and HTTP response is sent to the client with a status code indicating why the request was rejected. This rejection response was not fully initialised in the HTTP/2 protocol handler if the offending header was the very first one received or appeared in a a footer. This led to a NULL pointer dereference on initialised memory, crashing reliably the child process. Since such a triggering HTTP/2 request is easy to craft and submit, this can be exploited to DoS the server. This issue affected mod_http2 1.15.17 and Apache HTTP Server version 2.4.47 only. Apache HTTP Server 2.4.47 was never released.


Links NIST CIRCL RHEL Ubuntu

Severity

Severity Score
CVSS Version 2.x MEDIUM 5
CVSS Version 3.x HIGH 7.5

Status

OS name Project name Version Score Severity Status Errata Last updated

Statement

Ubuntu 16.04 ELS apache2 2.4.18 7.5 HIGH Not Vulnerable 2021-12-10 13:40:03