Security Bulletin
Summary
A Use After Free vulnerability may affect TXSeries for Multiplatforms (CVE-2025-38000). To address the vulnerability, the base container image for TXSeries for Multiplatforms has been updated to Red Hat Enterprise Linux (RHEL) Universal Base Image (UBI) 9 Minimal.
Vulnerability Details
CVEID: CVE-2025-38000
DESCRIPTION: In the Linux kernel, the following vulnerability has been resolved:
sch_hfsc: Fix qlen accounting bug when using peek in hfsc_enqueue()
When enqueuing the first packet to an HFSC class, hfsc_enqueue() calls the
child qdisc's peek() operation before incrementing sch-q.qlen and
sch-qstats.backlog. If the child qdisc uses qdisc_peek_dequeued(), this may
trigger an immediate dequeue and potential packet drop. In such cases,
qdisc_tree_reduce_backlog() is called, but the HFSC qdisc's qlen and backlog
have not yet been updated, leading to inconsistent queue accounting. This
can leave an empty HFSC class in the active list, causing further
consequences like use-after-free.
This patch fixes the bug by moving the increment of sch-q.qlen and
sch-qstats.backlog before the call to the child qdisc's peek() operation.
This ensures that queue length and backlog are always accurate when packet
drops or dequeues are triggered during the peek.
CWE: CWE-416: Use After Free
CVSS Source: NVD
CVSS Base score: 7.8
CVSS Vector: (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H)
Affected Products and Versions
| Affected Product(s) | Version(s) |
| IBM TXSeries for Multiplatforms | 11.1 |
Remediation/Fixes
IBM strongly recommends addressing the vulnerability now by downloading and applying the below fix.
| Product | Version | Platform | Remediation/Fix |
| IBM TXSeries for Multiplatforms |
11.1
|
Linux
[Container]
|
Download and apply the update from Fix Central |
Workarounds and Mitigations
None
Get Notified about Future Security Bulletins
References
Acknowledgement
Change History
29 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
Was this topic helpful?
Document Information
Modified date:
29 July 2026
Initial Publish date:
29 July 2026
UID
ibm17281764