Security Bulletin: Multiple vulnerabilities in IBM HTTP Server used by IBM WebSphere Application Server

Summary

There are multiple vulnerabilities in the IBM HTTP Server used by IBM WebSphere Application Server. This has been addressed. IBM HTTP Server is affected by CVE-2021-44224 for IBM HTTP Server configurations with “ProxyRequests ON” in the IBM HTTP Server configuration file (httpd.conf by default). IBM HTTP Server is affected by CVE-2021-44790 for IBM HTTP Server configurations with “LoadModule lua_module/mod_lua.so” appearing in the IBM HTTP Server configuration file (httpd.conf by default) where a customer-provided Lua script uses the “r:parsebody” function.

Vulnerability Details

CVEID:CVE-2021-44224
**DESCRIPTION:**Apache HTTP Server is vulnerable to a denial of service or server-side request forgery. By sending a specially crafted URI to httpd configured as a forward proxy, an attacker could exploit this vulnerability to cause a NULL pointer dereference. By sending a specially crafted URI to configurations mixing forward and reverse proxy declarations, an attacker could allow for requests to be directed to a declared Unix Domain Socket endpoint.
CVSS Base score: 8.2
CVSS Temporal Score: See: https://exchange.xforce.ibmcloud.com/vulnerabilities/215719 for the current score.
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H)

CVEID:CVE-2021-44790
**DESCRIPTION:**Apache HTTP Server is vulnerable to a buffer overflow, caused by improper bounds checking in the mod_lua multipart parser called from Lua scripts). By sending a specially crafted request, a remote attacker could overflow a buffer and execute arbitrary code on the system or cause the application to crash.
CVSS Base score: 9.8
CVSS Temporal Score: See: https://exchange.xforce.ibmcloud.com/vulnerabilities/215686 for the current score.
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H)

Affected Products and Versions

This vulnerability affects the following version and release of IBM HTTP Server (powered by Apache) component in all editions of IBM WebSphere Application Server and bundling products.

Remediation/Fixes

IBM strongly recommends addressing this vulnerability now by applying the interim fix or Fix Pack linked below containing APAR PH42862 for each named product.

For IBM HTTP Server used by IBM WebSphere Application Server:

For V9.0.0.0 through 9.0.5.10:

IBM strongly recommends addressing this vulnerability now by applying the interim fix or Fix Pack linked below containing APAR PH42862 for each named product.

· Upgrade to minimal fix pack levels as required by interim fix and then apply Interim Fix PH42862
--OR–
· Apply Fix Pack 9.0.5.11 or later (targeted availability 1Q2022).

Additional interim fixes may be available and linked off the interim fix download page.

Important Note

IBM strongly suggests that all System z customers be subscribed to the System z Security Portal to receive the latest critical System z security and
integrity service. If you are not subscribed, see the instructions on the System z Security web site. Security and integrity APARs and associated fixes will
be posted to this portal. IBM suggests reviewing the CVSS scores and applying all security or integrity fixes as soon as possible to minimize any potential
risk.

Workarounds and Mitigations

Mitigations for this issue are available. If the interim fixes in PH42862 cannot be applied immediately, then follow the temporary mitigation steps as documented in Interim Fix PH42862.