CVE-2026-99172
In the Linux kernel, the following vulnerability has been resolved: ipc: drop the mqueue mount with kern_unmount() on setup failure mq_init_ns() creates the mqueue mount with fc_mount_longterm(), so its ->mnt_ns is MNT_NS_INTERNAL. When setting up the mqueue or ipc sysctls or msg_init_ns() fails afterwards, create_ipc_ns() drops it with a plain mntput(). With ->mnt_ns set that takes the fast path of mntput_no_expire(). The count drops to zero and nothing ever kills the mount, so the mount and the mqueue superblock are leaked. Commit dc55e35f9e81 ("ipc: Store mqueue sysctls in the ipc namespace") added the first failure path after mq_init_ns() and never dropped the mount. Commit 7229d74e5e8c ("ipc: create_ipc_ns: drop mqueue mount on sysctl setup failure") tried to fix that with a mntput() but that doesn't help for a long-term mount. Use kern_unmount(). free_ipc() open-codes the same thing for a namespace that made it.
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:
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
Sources: NVD and CISA KEV when available. Vendor confirmation remains the final authority for fixed versions and workarounds.