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Security Bulletin: IBM i is Affected By Multiple Vulnerabilities in IBM WebSphere Application Server Liberty

Security Bulletin


Summary

IBM WebSphere Application Server Liberty for IBM i is vulnerable to denial-of-service (DoS) when processing a JSON document [CVE-2026-9563], improper synchronization using a shared resource [CVE-2026-5516], providing weaker than expected security [CVE-2025-14917], identity spoofing [CVE-2026-3621], DoS caused by sending a specially crafted request [CVE-2026-9071, CVE-2026-9320, CVE-2026-9322, CVE-2026-9171], HTTP request smuggling [CVE-2026-8646, CVE-2026-11541], and uncontrolled resource consumption or a denial of service attack [CVE-2026-50645] as described in the vulnerability details section.

Vulnerability Details

CVEID:   CVE-2026-9563
DESCRIPTION:   In Eclipse Parsson published Maven Central artifacts before version 1.1.8, the JSON parser did not enforce a default maximum on the number of characters consumed while parsing a single JSON document. Applications that parse attacker- controlled JSON can be forced to consume excessive CPU and memory by processing very large documents, including large arrays, objects, strings, numbers, whitespace, or nested structures, resulting in a denial of service. Eclipse Parsson 1.1.8 introduces a configurable maximum parsing limit with a default limit of 15 million parser-consumed characters.
CWE:   CWE-400: Uncontrolled Resource Consumption
CVSS Source:   emo@eclipse.org
CVSS Base score:   7.5
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)

CVEID:   CVE-2026-5516
DESCRIPTION:   IBM WebSphere Application Server - Liberty 22.0.0.11 through 26.0.0.5 IBM WebSphere Application Server Liberty could allow a remote attacker to bypass security under limited conditions by exploiting a specific timing window.
CWE:   CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
CVSS Source:   IBM
CVSS Base score:   4.4
CVSS Vector:   (CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:N/A:N)

CVEID:   CVE-2026-11541
DESCRIPTION:   IBM WebSphere Application Server 9.0, and 8.5 and IBM WebSphere Application Server - Liberty 17.0.0.3 through 26.0.0.6 are affected by an HTTP request smuggling vulnerability.
CWE:   CWE-444: Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')
CVSS Source:   IBM
CVSS Base score:   7.4
CVSS Vector:   (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N)

CVEID:   CVE-2026-3621
DESCRIPTION:   IBM WebSphere Application Server - Liberty 17.0.0.3 through 26.0.0.4 IBM WebSphere Application Server Liberty is vulnerable to identity spoofing under limited conditions when an application is deployed without authentication and authorization configured.
CWE:   CWE-269: Improper Privilege Management
CVSS Source:   IBM
CVSS Base score:   7.5
CVSS Vector:   (CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H)

CVEID:   CVE-2026-9071
DESCRIPTION:   IBM WebSphere Application Server 9.0, and 8.5 and IBM WebSphere Application Server - Liberty 17.0.0.3 through 26.0.0.6 are vulnerable to a denial of service, caused by sending a specially-crafted request. A remote attacker could exploit this vulnerability to cause the server to consume memory resources.
CWE:   CWE-400: Uncontrolled Resource Consumption
CVSS Source:   IBM
CVSS Base score:   7.5
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)

CVEID:   CVE-2025-14917
DESCRIPTION:   IBM WebSphere Application Server - Liberty 17.0.0.3 through 26.0.0.3 IBM WebSphere Application Server Liberty could provide weaker than expected security when administering security settings.
CWE:   CWE-1393: Use of Default Password
CVSS Source:   IBM
CVSS Base score:   6.7
CVSS Vector:   (CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H)

CVEID:   CVE-2026-50645
DESCRIPTION:   There is no restriction on the amount of attachment headers that a message can contain when being deserialized by Apache CXF, which can lead to uncontrolled resource consumption or a denial of service attack. Users are recommended to upgrade to versions 4.2.2 or 4.1.7, which fix this issue by imposing a maximum default of 500 attachments per message.
CWE:   CWE-400: Uncontrolled Resource Consumption
CVSS Source:   NVD
CVSS Base score:   7.5
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)

CVEID:   CVE-2026-9322
DESCRIPTION:   IBM WebSphere Application Server and WebSphere Application Server Liberty are vulnerable to a denial of service via a crafted HTTP request.
CWE:   CWE-400: Uncontrolled Resource Consumption
CVSS Source:   IBM
CVSS Base score:   7.5
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)

CVEID:   CVE-2026-9171
DESCRIPTION:   IBM PowerVM Novalink are vulnerable to a denial of service, caused by sending a specially-crafted request. A remote attacker could exploit this vulnerability to cause the server to consume memory resources.
CWE:   CWE-400: Uncontrolled Resource Consumption
CVSS Source:   IBM
CVSS Base score:   7.5
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)

CVEID:   CVE-2026-9320
DESCRIPTION:   IBM WebSphere Application Server 9.0, and 8.5 and IBM WebSphere Application Server - Liberty 17.0.0.3 through 26.0.0.6 are vulnerable to a denial of service, caused by sending a specially-crafted request. A remote attacker could exploit this vulnerability to cause the server to consume memory resources.
CWE:   CWE-400: Uncontrolled Resource Consumption
CVSS Source:   IBM
CVSS Base score:   5.9
CVSS Vector:   (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H)

CVEID:   CVE-2026-8646
DESCRIPTION:   IBM WebSphere Application Server 9.0 and 8.5 and IBM WebSphere Application Server - Liberty 17.0.0.3 through 26.0.0.6 are vulnerable to HTTP request smuggling. A remote attacker could smuggle a specially crafted request to the application server thereby allowing the attacker to bypass security controls, spoof identity, escalate privilege, and expose sensitive information.
CWE:   CWE-444: Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')
CVSS Source:   IBM
CVSS Base score:   8.1
CVSS Vector:   (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N)

Affected Products and Versions

Affected Product(s)Version(s)
IBM i7.6
IBM i7.5
IBM i7.4
IBM i7.3

Remediation/Fixes

IBM i Release5770-SS1 Option 3
PTF Number(s)
PTF Download Link(s)
7.6SJ10146https://www.ibm.com/mysupport/s/fix-information?legacy=SJ10146
7.5SJ10147https://www.ibm.com/mysupport/s/fix-information?legacy=SJ10147
7.4SJ10148https://www.ibm.com/mysupport/s/fix-information?legacy=SJ10148
7.3SJ10149https://www.ibm.com/mysupport/s/fix-information?legacy=SJ10149

IBM recommends users running unsupported versions of affected products upgrade to a supported and fixed version of affected products.

Workarounds and Mitigations

None

Get Notified about Future Security Bulletins

References

Off

Acknowledgement

Change History

22 Jul 2026: Initial Publication

*The CVSS Environment Score is customer environment specific and will ultimately impact the Overall CVSS Score. Customers can evaluate the impact of this vulnerability in their environments by accessing the links in the Reference section of this Security Bulletin.

Disclaimer

According to the Forum of Incident Response and Security Teams (FIRST), the Common Vulnerability Scoring System (CVSS) is an "industry open standard designed to convey vulnerability severity and help to determine urgency and priority of response." IBM PROVIDES THE CVSS SCORES ""AS IS"" WITHOUT WARRANTY OF ANY KIND, INCLUDING THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. CUSTOMERS ARE RESPONSIBLE FOR ASSESSING THE IMPACT OF ANY ACTUAL OR POTENTIAL SECURITY VULNERABILITY. In addition to other efforts to address potential vulnerabilities, IBM periodically updates the record of components contained in our product offerings. As part of that effort, if IBM identifies previously unidentified packages in a product/service inventory, we address relevant vulnerabilities regardless of CVE date. Inclusion of an older CVEID does not demonstrate that the referenced product has been used by IBM since that date, nor that IBM was aware of a vulnerability as of that date. We are making clients aware of relevant vulnerabilities as we become aware of them. "Affected Products and Versions" referenced in IBM Security Bulletins are intended to be only products and versions that are supported by IBM and have not passed their end-of-support or warranty date. Thus, failure to reference unsupported or extended-support products and versions in this Security Bulletin does not constitute a determination by IBM that they are unaffected by the vulnerability. Reference to one or more unsupported versions in this Security Bulletin shall not create an obligation for IBM to provide fixes for any unsupported or extended-support products or versions.

Document Location

Worldwide

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Document Information

Modified date:
22 July 2026

Initial Publish date:
22 July 2026

UID

ibm17280782