CVE-2026-99156
In the Linux kernel, the following vulnerability has been resolved: scsi: st: Fix use-after-free race between st_remove() and st_open() st_remove() drops the probe reference on the scsi_tape with kref_put() and only afterwards removes its index from st_index_idr. If that was the last reference, scsi_tape_release() frees the structure while it is still published in the idr. scsi_tape_get(), called from st_open(), looks up the tape in st_index_idr and takes a reference under st_ref_mutex and st_index_lock. remove_cdevs() does not wait for opens that are already past chrdev_open(), so an open that is blocked on st_ref_mutex while st_remove() holds it can take the mutex as soon as st_remove() drops it, find the freed tpnt in the idr and call kref_get() on it: BUG: KASAN: slab-use-after-free in st_open Write of size 4 ... st_open (drivers/scsi/st.c:254 drivers/scsi/st.c:1291) chrdev_open ... Freed by task ...: kfree st_remove (drivers/scsi/st.c:4512) Remove the index from the idr before dropping the reference, all under st_ref_mutex. A concurrent scsi_tape_get() now either runs first and holds a valid reference that keeps the tape alive, or runs afterwards and finds nothing, so st_open() fails with -ENXIO. This restores the ordering st_remove() had before the conversion to st_index_idr, where the tape was unpublished from scsi_tapes[] before the final kref_put().
Executive briefing
This record describes a reported software or hardware weakness. The description and CVSS rating are source metadata; practical risk depends on whether your environment uses an affected product/version and whether the vulnerable component is reachable and configured in an exploitable way.
Severity & exploitability
CVSS vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Impacted products and platforms
Specific affected product configurations are not currently available in the NVD record. Review vendor advisories and validate applicability against your asset inventory.
How it works and what it could affect
The NVD description is the authoritative short summary currently available for this record. A detailed technical mechanism is not inferred when the source record does not provide one.
Review the CVSS attack characteristics above to understand whether exploitation is network/local, whether privileges or user interaction are required, and which confidentiality, integrity or availability impacts are scored.
Remediation and recommended response
- Identify exposure: compare the affected product and version ranges below with your asset inventory, software bill of materials, endpoint inventory and externally exposed services.
- Remediate: review the linked vendor security advisory or patch notes, upgrade to a fixed release, or apply the vendor-provided workaround if an upgrade cannot be completed.
- Mitigate while patching: restrict network access to the vulnerable service, disable the affected feature where operationally safe, and monitor vendor/CERT advisories for updated guidance.
- Validate: confirm the fixed version or mitigation on representative systems, run a vulnerability rescan, and retain change evidence.
No vendor remediation link has been identified in the available NVD references yet. Check the affected vendor's security advisory portal before applying changes.
Exploit intelligence & references
No CISA KEV match is recorded in the latest successful catalog refresh. This is not a guarantee that public proof-of-concept code or exploitation does not exist.
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67 reference
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67 reference
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67 reference
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67 reference
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67 reference
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67 reference
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67 reference
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67 reference
Sources: NVD and CISA KEV when available. Vendor confirmation remains the final authority for fixed versions and workarounds.