IBM WebSphere Application Server 9.x < 9.0.5.30 (7292227)

high Nessus Plugin ID 379784

Synopsis

The remote web application server is affected by a vulnerability.

Description

The version of IBM WebSphere Application Server running on the remote host is affected by a vulnerability as referenced in the 7292227 advisory.

- js-yaml is a JavaScript YAML parser and dumper. From 3.0.0 until 3.15.2, 4.3.2, and 5.4.1, maxTotalMergeKeys in lib/js-yaml/loader.js and lib/loader.js does not count empty mapping sources while processing the merge key <<. An attacker can alias a large sequence of empty mappings into many merge targets, causing O(N * K) processing while totalMergeKeys remains unchanged and the configured resource limit is never reached. A relatively small YAML document can therefore cause prolonged CPU consumption in applications that parse untrusted YAML, and merge processing is enabled by default on these release lines.
In v3 & v4, merge is enabled by default so the severity score is higher. This issue is fixed in versions 3.15.2, 4.3.2, and 5.4.1. (CVE-2026-84375)

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

Solution

Update to IBM WebSphere Application Server version 9.0.5.30 or later.

See Also

https://www.ibm.com/support/pages/node/7292227

Plugin Details

Severity: High

ID: 379784

File Name: websphere_7292227.nasl

Version: 1.1

Type: Combined

Agent: windows, macosx, unix

Family: Web Servers

Published: 11/12/2026

Updated: 11/12/2026

Configuration: Enable thorough checks (optional)

Supported Sensors: Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 5.7

Percentile: 96.05

CVSS v2

Risk Factor: High

Base Score: 7.8

Temporal Score: 5.8

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:C

CVSS Score Source: CVE-2026-84375

CVSS v3

Risk Factor: High

Base Score: 7.5

Temporal Score: 6.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/a:ibm:websphere_application_server

Required KB Items: installed_sw/IBM WebSphere Application Server

Exploit Ease: No known exploits are available

Patch Publication Date: 10/13/2026

Vulnerability Publication Date: 9/1/2026

Reference Information

CVE: CVE-2026-84375