Security Bulletin: IBM i is vulnerable to a denial of service caused by a memory corruption in the deflate operation of Zlib (CVE-2018-25032)

Summary

IBM i uses Zlib for GeoMirror, Save/Restore, and Main Storage Dump compression. Zlib is vulnerable to a denial of service attack caused by a memory corruption in the deflate operation as described in the vulnerability details section. IBM i has addressed the vulnerability in Zlib with a fix as described in the remediation/fixes section.

Vulnerability Details

CVEID:CVE-2018-25032
**DESCRIPTION:**Zlib is vulnerable to a denial of service, caused by a memory corruption in the deflate operation. By using many distant matches, a remote attacker could exploit this vulnerability to cause the application to crash.
CVSS Base score: 7.5
CVSS Temporal Score: See: https://exchange.xforce.ibmcloud.com/vulnerabilities/222615 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 and 7.4 will be fixed.

The IBM i PTF numbers contain the fix for the vulnerability.

IBM i Release| 5770-999
PTF Number| PTF Download Link
—|—|—
7.5| MF70403| MF70403
7.4| MF70398| MF70398

<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