Synopsis
The remote web server is affected by multiple vulnerabilities.
Description
The version of Apache httpd installed on the remote host is prior to 2.4.58. It is, therefore, affected by multiple vulnerabilities as referenced in the 2.4.58 advisory.
- Apache HTTP Server: DoS in HTTP/2 with initial windows size 0: 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.
Acknowledgements: (CVE-2023-43622)
- Apache HTTP Server: HTTP/2 stream memory not reclaimed right away on RST: When a HTTP/2 stream was reset (RST frame) by a client, there was a time window were the request's memory resources were not reclaimed immediately. Instead, de-allocation was deferred to connection close. A client could send new requests and resets, keeping the connection busy and open and causing the memory footprint to keep on growing. On connection close, all resources were reclaimed, but the process might run out of memory before that. This was found by the reporter during testing of CVE-2023-44487 (HTTP/2 Rapid Reset Exploit) with their own test client. During normal HTTP/2 use, the probability to hit this bug is very low. The kept memory would not become noticeable before the connection closes or times out. Users are recommended to upgrade to version 2.4.58, which fixes the issue. Acknowledgements: (CVE-2023-45802)
Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.
Solution
Upgrade to Apache version 2.4.58 or later.
Plugin Details
File Name: apache_2_4_58.nasl
Agent: windows, macosx, unix
Supported Sensors: Frictionless Assessment AWS, Frictionless Assessment Azure, Frictionless Assessment Agent, Nessus Agent, Nessus
Risk Information
Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:C
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C
Vulnerability Information
CPE: cpe:/a:apache:http_server, cpe:/a:apache:httpd
Required KB Items: installed_sw/Apache
Exploit Ease: No known exploits are available
Patch Publication Date: 10/19/2023
Vulnerability Publication Date: 9/15/2023