Read the docs
TI-2026-81879 Aliases CVE-2026-99172GHSA-c64w-44gc-4h7w

Mqueue mount leak in Linux kernel IPC namespace setup failure

Priority LOW 22Published · Updated

Key facts

Attack vector
—
Privileges required
—
User interaction
—
Attack complexity
—
Impact type
—
Confidentiality · integrity · availability
—
Fix status
Partial Red Hat: 5 without a fix

No CVSS vector from any source. Fix status from CNA and Red Hat.

Summary

The Linux kernel from 5.19 is affected by a resource leak in IPC namespace creation. When setup of the mqueue or IPC sysctls, or msg_init_ns(), fails after the mqueue mount is created, create_ipc_ns() drops the mount with mntput(), which never unmounts it, so the mount and the mqueue superblock leak.

Written with Claude Haiku 5.5 from the sources below · 2026-11-07

Description from the CNA

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.

Why it matters now

EPSS 0.00172 6th percentileScored 2026-11-07
Fix Partial Linux (Linux): 6.18.61, 7.2.13, 7.3Red Hat: 5 without a fix

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux5.19 and later6.18.61, 7.2.13, 7.3Patch availableCNA
  • Linux VendorLinux Affected 5.19 and later Fixed in 6.18.61, 7.2.13, 7.3 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*——Linux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions — — ·Linux

Remediation

Upgrade the Linux kernel to 6.18.61, 7.2.13 or 7.3, which contain the fix. Red Hat lists Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 and Red Hat OpenShift Container Platform 5 as affected with no fix available, and Red Hat Enterprise Linux 6 as affected with no fix planned.

Written with Claude Haiku 5.5 from the sources below · 2026-11-07

  • Fix · CNA Linux (Linux) Fixed in 6.18.61, 7.2.13, 7.3

Vendor assessments

Red Hat

Red Hat rating: Low. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 10AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 6AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 9AffectedNo fix yet: Fix deferred
Red Hat OpenShift Container Platform 4AffectedNo fix yet: Fix deferred
Red Hat OpenShift Container Platform 5AffectedNo fix yet: Fix deferred
Not affected: 4 products
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux 8
  • Red Hat Enterprise Linux 9
  • Red Hat OpenShift Container Platform 4

Timeline

  1. 2026-10-28 Threatist record created from CVE-2026-99172
  2. 2026-10-28 Alias added: GHSA-c64w-44gc-4h7w
  3. 2026-10-29 Affected versions changed · Red Hat
  4. 2026-10-29 CVSS score added · Red Hat
  5. 2026-11-06 Fix available: Linux/Linux@4aef6ceb4d6acacd53bc047ac4849677c3edbec1, Linux/[email protected] · CNA
  6. 2026-11-06 1 new reference · CNA
  7. 2026-11-07 Affected versions changed · Red Hat

References

Other 3

  • TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
  • TI-2021-02452 Incorrect authorization in Ubuntu linux kernel KEVCVSS 3.1HIGH 8.8
  • TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
  • TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
  • TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
See all 21741 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences