The version of httpd installed on the remote host is prior to 2.4.51-1. It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2-2021-1716 advisory.

    A NULL pointer dereference was found in Apache httpd mod_h2. The highest threat from this flaw is to     system integrity. (CVE-2021-33193)

    A NULL pointer dereference in httpd allows an unauthenticated remote attacker to crash httpd by providing     malformed HTTP requests. The highest threat from this vulnerability is to system availability.
    (CVE-2021-34798)

    An out-of-bounds read in mod_proxy_uwsgi of httpd allows a remote unauthenticated attacker to crash the     service through a crafted request. The highest threat from this vulnerability is to system availability.
    (CVE-2021-36160)

    An out-of-bounds write in function ap_escape_quotes of httpd allows an unauthenticated remote attacker to     crash the server or potentially execute code on the system with the privileges of the httpd user, by     providing malicious input to the function. (CVE-2021-39275)

    A Server-Side Request Forgery (SSRF) flaw was found in mod_proxy of httpd. This flaw allows a remote,     unauthenticated attacker to make the httpd server forward requests to an arbitrary server. The attacker     could get, modify, or delete resources on other services that may be behind a firewall and inaccessible     otherwise. The impact of this flaw varies based on what services and resources are available on the httpd     network. (CVE-2021-40438)

    While fuzzing the 2.4.49 httpd, a new null pointer dereference was detected during HTTP/2 request     processing, allowing an external source to DoS the server. This requires a specially crafted request. The     vulnerability was recently introduced in version 2.4.49. No exploit is known to the project.
    (CVE-2021-41524)

    A path transversal flaw was found in Apache 2.4.49. A remote attacker could use this flaw to map URLs to     files outside the expected document root. Additionally this flaw could leak the source of interpreted     files like CGI scripts. (CVE-2021-41773)

    A path transversal and remote code execution flaw was found in Apache HTTP Server 2.4.49 and 2.4.50. A     remote attacker could use this flaw to map URLs to files outside the expected document root. Additionally,     this flaw could leak the source of interpreted files like CGI scripts. If files outside of these     directories are not protected by the usual default configuration require all denied, these requests can     succeed. If CGI scripts are also enabled for these aliased paths, this could allow for remote code     execution. The highest threat from this vulnerability is to data confidentiality and integrity as well as     system availability. This is an incomplete fix for CVE-2021-41773. (CVE-2021-42013)

Tenable has extracted the preceding description block directly from the tested product security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

Detections

Analytics

Amazon Linux 2 : httpd (ALAS-2021-1716)

critical Nessus Plugin ID 154179

Version 1.16

Version 1.15

Version 1.14

Version 1.13

Version 1.16 Dec 12, 2024, 9:55 AM CVSS metrics ("Cvssv4 score" set to 0.0) CVSSv2 severity (based on None, severity decreased from "High" to "Low") Detection (updated detection logic) Plugin metadata Plugin Feed: 202412120955
Version 1.15 Jan 18, 2024, 8:01 PM CVSS temporal metrics ("CVSSv2 temporal vector" set to "CVSS2#E:H/RL:OF/RC:C". "CVSSv3 temporal vector" set to "CVSS:3.0/E:H/RL:O/RC:C") Exploit attributes ("Exploited by malware" set to "True") Plugin Feed: 202401182001
Version 1.14 Apr 25, 2023, 11:11 PM CVSS temporal metrics (Adjust exploitability metrics for CISA KEV vulnerabilities) Plugin Feed: 202304252311
Version 1.13 Dec 6, 2022, 4:40 AM Reference Plugin Feed: 202212060440