vulnerability

Apache HTTPD: CVE-2023-43622: Uncontrolled Resource Consumption

Severity
8
CVSS
(AV:N/AC:L/Au:N/C:N/I:N/A:C)
Published
Oct 23, 2023
Added
Nov 29, 2023
Modified
Apr 9, 2026

Description

An attacker, opening a HTTP/2 connection with an initial window size of 0, was able to block handling of that connection indefinitely in Apache HTTP Server. This could be used to exhaust worker resources in the server, similar to the well known "slow loris" attack pattern.
This has been fixed in version 2.4.58, so that such connection are terminated properly after the configured connection timeout.

This issue affects Apache HTTP Server: from 2.4.55 through 2.4.57.

Users are recommended to upgrade to version 2.4.58, which fixes the issue.

Solution

apache-httpd-upgrade-latest
Title
Rapid7 Labs

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