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Security Bulletin: Due to the use of IBM WebSphere Liberty, IBM TXSeries for Multiplatforms is vulnerable to a flaw in handling multiplexed streams in the HTTP/2 protocol (CVE-2023-44487).

Security Bulletin


IBM WebSphere Liberty is used by IBM TXSeries for Multiplatforms to provide a web based administration console (CVE-2023-44487).

Vulnerability Details

CVEID:   CVE-2023-44487
DESCRIPTION:   Multiple vendors are vulnerable to a denial of service, caused by a flaw in handling multiplexed streams in the HTTP/2 protocol. By sending numerous HTTP/2 requests and RST_STREAM frames over multiple streams, a remote attacker could exploit this vulnerability to cause a denial of service due to server resource consumption.
CVSS Base score: 7.5
CVSS Temporal Score: See: 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

Affected Product(s)Version(s)
IBM TXSeries for Multiplatforms8.1
IBM TXSeries for Multiplatforms8.2
IBM TXSeries for Multiplatforms9.1



IBM strongly recommends addressing the vulnerability now by upgrading IBM CICS TXSeries for Multiplatforms.

IBM TXSeries for Multiplatforms8.1Linux, AIX

PSIRT fixes for TXSeries 8.1 will be provided only for extended support customers with a request through Salesforce case

IBM TXSeries for Multiplatforms8.2Linux, Windows, AIXDownload the upgrade from Fix Central
IBM TXSeries for Multiplatforms9.1Linux, AIXDownload the upgrade from Fix Central


Workarounds and Mitigations


Get Notified about Future Security Bulletins




Change History

23 Jan 2024: 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.


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


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Document Information

Modified date:
13 March 2024