Security Bulletin: OpenSSL for IBM i is vulnerable to denial of service attacks and the ability for remote attacker to obtain sensitive information due to multiple vulnerabilities.

Summary

OpenSSL for IBM i is vulnerable to a denial of service caused by error in certificate verification (CVE-2023-0464), a denial of service caused by arbitrary pointers to memcmp (CVE-2023-0286), denial of service caused by a double-free error (CVE-2022-4450), denial of service caused by use-after-free error (CVE-2023-0215), and the ability for a remote attack to obtain sensitive information caused by a timing-based side channel in RSA decryption (CVE-2022-4304) as described in the vulnerability details section. IBM i has addressed the vulnerabilities in OpenSSL with a fix as described in the remediation/fixes section.

Vulnerability Details

CVEID:CVE-2023-0464
**DESCRIPTION:**OpenSSL is vulnerable to a denial of service, caused by an error related to the verification of X.509 certificate chains that include policy constraints. By creating a specially crafted certificate chain that triggers exponential use of computational resources, a remote attacker could exploit this vulnerability to cause a denial of service.
CVSS Base score: 5.3
CVSS Temporal Score: See: https://exchange.xforce.ibmcloud.com/vulnerabilities/250736 for the current score.
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L)

CVEID:CVE-2023-0286
**DESCRIPTION:**OpenSSL is vulnerable to a denial of service, caused by a type confusion error related to X.400 address processing inside an X.509 GeneralName. By passing arbitrary pointers to a memcmp call, a remote attacker could exploit this vulnerability to read memory contents or cause a denial of service.
CVSS Base score: 8.2
CVSS Temporal Score: See: https://exchange.xforce.ibmcloud.com/vulnerabilities/246611 for the current score.
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H)

CVEID:CVE-2022-4450
**DESCRIPTION:**OpenSSL is vulnerable to a denial of service, caused by a double-free error related to the improper handling of specific PEM data by the PEM_read_bio_ex() function. By sending specially crafted PEM files for parsing, a remote attacker could exploit this vulnerability to cause the system to crash.
CVSS Base score: 7.5
CVSS Temporal Score: See: https://exchange.xforce.ibmcloud.com/vulnerabilities/246615 for the current score.
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)

CVEID:CVE-2022-4304
**DESCRIPTION:**OpenSSL could allow a remote attacker to obtain sensitive information, caused by a timing-based side channel in the RSA Decryption implementation. By sending an overly large number of trial messages for decryption, an attacker could exploit this vulnerability to obtain sensitive information.
CVSS Base score: 7.5
CVSS Temporal Score: See: https://exchange.xforce.ibmcloud.com/vulnerabilities/246612 for the current score.
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N)

CVEID:CVE-2023-0215
**DESCRIPTION:**OpenSSL is vulnerable to a denial of service, caused by a use-after-free error related to the incorrect handling of streaming ASN.1 data by the BIO_new_NDEF function. A remote attacker could exploit this vulnerability to cause a denial of service.
CVSS Base score: 7.5
CVSS Temporal Score: See: https://exchange.xforce.ibmcloud.com/vulnerabilities/246614 for the current score.
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)

Affected Products and Versions

Remediation/Fixes

The issue can be fixed by applying a PTF to IBM i. IBM i releases 7.5, 7.4, 7.3, and 7.2 will be fixed.

The IBM i PTF numbers for OpenSSL in 5733-SC1 contain the fixes for the vulnerabilities.

IBM i Release| 5733-SC1
PTF Number| PTF Download Link
—|—|—
7.5| SI83245| <https://www.ibm.com/support/pages/ptf/SI83245&gt;
7.4, 7.3, 7.2| SI83194| <https://www.ibm.com/support/pages/ptf/SI83194&gt;

<https://www.ibm.com/support/fixcentral&gt;

Important note: IBM recommends that all users running unsupported versions of affected products upgrade to supported and fixed version of affected products.

Workarounds and Mitigations

None