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

Summary

There are multiple vulnerabilities in the Expat library affecting the IBM HTTP Server used by IBM WebSphere Application Server (CVE-2021-45960, CVE-2022-22822, CVE-2022-23990, CVE-2022-22823, CVE-2022-23852, CVE-2022-22825, CVE-2021-46143, CVE-2022-22824, CVE-2022-22826, and CVE-2022-22827). This has been addressed.

Vulnerability Details

CVEID:CVE-2021-45960
**DESCRIPTION:**Expat (aka libexpat) is vulnerable to a denial of service, caused by a realloc misbehavior issue in the storeAtts function in xmlparse.c. By persuading a victim to open a specially-crafted XML content, a remote attacker could exploit this vulnerability to cause a the application to crash.
CVSS Base score: 5.5
CVSS Temporal Score: See: https://exchange.xforce.ibmcloud.com/vulnerabilities/216473 for the current score.
CVSS Vector: (CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H)

CVEID:CVE-2022-22822
**DESCRIPTION:**Expat could allow a remote attacker to execute arbitrary code on the system, caused by an integer overflow of addBinding in xmlparse.c. By persuading a victim to open a specially-crafted file, an attacker could exploit this vulnerability to execute arbitrary code on the system.
CVSS Base score: 7.8
CVSS Temporal Score: See: https://exchange.xforce.ibmcloud.com/vulnerabilities/216908 for the current score.
CVSS Vector: (CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H)

CVEID:CVE-2022-23990
**DESCRIPTION:**Expat (aka libexpat) could allow a remote attacker to execute arbitrary code on the system, caused by an integer overflow in the doProlog function. By sending a specially-crafted request, an attacker could exploit this vulnerability to execute arbitrary code on the system.
CVSS Base score: 9.8
CVSS Temporal Score: See: https://exchange.xforce.ibmcloud.com/vulnerabilities/218206 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)

CVEID:CVE-2022-22823
**DESCRIPTION:**Expat could allow a remote attacker to execute arbitrary code on the system, caused by an integer overflow of build_model in xmlparse.c. By persuading a victim to open a specially-crafted file, an attacker could exploit this vulnerability to execute arbitrary code on the system.
CVSS Base score: 7.8
CVSS Temporal Score: See: https://exchange.xforce.ibmcloud.com/vulnerabilities/216907 for the current score.
CVSS Vector: (CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H)

CVEID:CVE-2022-23852
**DESCRIPTION:**Expat (aka libexpat) could allow a remote attacker to execute arbitrary code on the system, caused by an integer overflow in the XML_GetBuffer function. By sending a specially-crafted request, an attacker could exploit this vulnerability to execute arbitrary code on the system.
CVSS Base score: 9.8
CVSS Temporal Score: See: https://exchange.xforce.ibmcloud.com/vulnerabilities/218007 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)

CVEID:CVE-2022-22825
**DESCRIPTION:**Expat could allow a remote attacker to execute arbitrary code on the system, caused by an integer overflow of lookup in xmlparse.c. By persuading a victim to open a specially-crafted file, an attacker could exploit this vulnerability to execute arbitrary code on the system.
CVSS Base score: 7.8
CVSS Temporal Score: See: https://exchange.xforce.ibmcloud.com/vulnerabilities/216905 for the current score.
CVSS Vector: (CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H)

CVEID:CVE-2021-46143
**DESCRIPTION:**Expat could allow a remote attacker to execute arbitrary code on the system, caused by an integer overflow of m_groupSize in doProlog in xmlparse.c. By persuading a victim to open a specially-crafted file, an attacker could exploit this vulnerability to execute arbitrary code on the system.
CVSS Base score: 7.8
CVSS Temporal Score: See: https://exchange.xforce.ibmcloud.com/vulnerabilities/216875 for the current score.
CVSS Vector: (CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H)

CVEID:CVE-2022-22824
**DESCRIPTION:**Expat could allow a remote attacker to execute arbitrary code on the system, caused by an integer overflow of defineAttribute in xmlparse.c. By persuading a victim to open a specially-crafted file, an attacker could exploit this vulnerability to execute arbitrary code on the system.
CVSS Base score: 7.8
CVSS Temporal Score: See: https://exchange.xforce.ibmcloud.com/vulnerabilities/216906 for the current score.
CVSS Vector: (CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H)

CVEID:CVE-2022-22826
**DESCRIPTION:**Expat could allow a remote attacker to execute arbitrary code on the system, caused by an integer overflow of nextScaffoldPart in xmlparse.c. By persuading a victim to open a specially-crafted file, an attacker could exploit this vulnerability to execute arbitrary code on the system.
CVSS Base score: 7.8
CVSS Temporal Score: See: https://exchange.xforce.ibmcloud.com/vulnerabilities/216904 for the current score.
CVSS Vector: (CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H)

CVEID:CVE-2022-22827
**DESCRIPTION:**Expat could allow a remote attacker to execute arbitrary code on the system, caused by an integer overflow of storeAtts in xmlparse.c. By persuading a victim to open a specially-crafted file, an attacker could exploit this vulnerability to execute arbitrary code on the system.
CVSS Base score: 7.8
CVSS Temporal Score: See: https://exchange.xforce.ibmcloud.com/vulnerabilities/216901 for the current score.
CVSS Vector: (CVSS:3.0/AV:L/AC:L/PR:N/UI:R/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 the vulnerability now by applying a currently available interim fix or fix pack that contains APAR PH43122.

For IBM HTTP Server used by IBM WebSphere Application Server:

For V9.0.0.0 through 9.0.5.10:
· Upgrade to minimal fix pack levels as required by interim fix and then apply Interim Fix PH43122
--OR–
· Apply Fix Pack 9.0.5.11 or later (targeted availability 1Q2022).

For V8.5.0.0 through 8.5.5.21:
· Upgrade to minimal fix pack levels as required by interim fix and then apply Interim Fix PH43122
--OR–
· Apply Fix Pack 8.5.5.22 or later (targeted availability 3Q2022).

For V8.0.0.0 through 8.0.0.15:
· Upgrade to 8.0.0.15 and then apply Interim Fix PH43122

For V7.0.0.0 through 7.0.0.45:
· Upgrade to 7.0.0.45 and then apply Interim Fix PH43122

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

_IBM HTTP Server V7.0 and V8.0 are no longer in full support; IBM recommends upgrading to a fixed, supported version/release/platform of the product. _

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

None