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TI-2026-61079 Aliases CVE-2026-90036GHSA-j6h5-vv56-hq58

NFSD: Prevent client use-after-free during blocked-lock reaping

Priority MEDIUM 43Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 17 fixed, 5 without a fix

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat.

Summary

In the Linux kernel, the following vulnerability has been resolved: NFSD: Prevent client use-after-free during blocked-lock reaping A bare lock owner -- its only remaining reference a blocked lock on nn->blocked_locks_lru -- holds a raw pointer to its nfs4_client but no reference keeping the client alive. When the per-net laundromat reaps such a lock, freeing the nbl drops the owner reference held through flc_owner, and the final nfs4_put_stateowner() takes the client's cl_lock. Because the laundromat detaches the nbl first, __destroy_client() no longer finds it, so a concurrent force_expire_client() can free the client before nfs4_put_stateowner() runs, dereferencing cl_lock in freed memory. Pin the client with cl_rpc_users before dropping nn->blocked_locks_lock, and skip clients already expiring, whose blocked locks __destroy_client() frees while holding an owner reference. Take nn->client_lock outside nn->blocked_locks_lock. Every other site holds nn->blocked_locks_lock as a leaf, acquiring no further lock, so placing nn->client_lock outside it cannot form a lock-order cycle.

Why it matters now

EPSS 0.00484 41st percentileScored 2026-11-07
Fix Partial Linux (Linux): 6.6.160, 6.12.111, 6.18.51 +2Red Hat: 5 advisoriesRed Hat: 17 fixed, 5 without a fix

SSVC decision points

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

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux4.9 and later6.6.160, 6.12.111, 6.18.51, 7.2.5, 7.3Patch availableCNA
  • Linux VendorLinux Affected 4.9 and later Fixed in 6.6.160, 6.12.111, 6.18.51, 7.2.5, 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

  • Fix · CNA Linux (Linux) Fixed in 6.6.160, 6.12.111, 6.18.51, 7.2.5, 7.3

Red Hat 5 advisories

  • RHSA-2026:89197 Released 2026-10-27 · Red Hat rating Critical
    OpenShift Container Platform 4.22.20 bug fix and security update
    • Red Hat OpenShift Container Platform 4.22 rhcos-aarch64-4.22.9.8.202610241758-0, rhcos-ppc64le-4.22.9.8.202610241758-0, rhcos-s390x-4.22.9.8.202610241758-0 +1
  • RHSA-2026:83207 Released 2026-10-15 · Red Hat rating Important
    kernel security, bug fix, and enhancement update
    • 10Base-SMTV kernel-modules-internal-6.12.0-211.66.1.el10_2
    • Red Hat Enterprise Linux AppStream (v. 10) kernel-64k-debug-devel-6.12.0-211.66.1.el10_2, kernel-64k-debug-devel-matched-6.12.0-211.66.1.el10_2, kernel-64k-devel-6.12.0-211.66.1.el10_2 +12
    • Red Hat Enterprise Linux BaseOS (v. 10) kernel-6.12.0-211.66.1.el10_2, kernel-64k-6.12.0-211.66.1.el10_2, kernel-64k-core-6.12.0-211.66.1.el10_2 +29
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) kernel-tools-libs-devel-6.12.0-211.66.1.el10_2, libperf-6.12.0-211.66.1.el10_2
    • Red Hat Enterprise Linux Hidden (v. 10) kernel-modules-internal-6.12.0-211.66.1.el10_2
    • Red Hat Enterprise Linux Real Time (v. 10) kernel-rt-6.12.0-211.66.1.el10_2, kernel-rt-64k-6.12.0-211.66.1.el10_2, kernel-rt-64k-core-6.12.0-211.66.1.el10_2 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 10) kernel-rt-6.12.0-211.66.1.el10_2, kernel-rt-core-6.12.0-211.66.1.el10_2, kernel-rt-debug-6.12.0-211.66.1.el10_2 +9
  • RHSA-2026:83156 Released 2026-10-14 · Red Hat rating Important
    kernel security update
    • Red Hat Enterprise Linux AppStream (v. 9) kernel-64k-debug-devel-5.14.0-687.58.1.el9_8, kernel-64k-debug-devel-matched-5.14.0-687.58.1.el9_8, kernel-64k-devel-5.14.0-687.58.1.el9_8 +12
    • Red Hat Enterprise Linux BaseOS (v. 9) kernel-5.14.0-687.58.1.el9_8, kernel-64k-5.14.0-687.58.1.el9_8, kernel-64k-core-5.14.0-687.58.1.el9_8 +28
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) kernel-tools-libs-devel-5.14.0-687.58.1.el9_8, libperf-5.14.0-687.58.1.el9_8
    • Red Hat Enterprise Linux Real Time (v. 9) kernel-rt-5.14.0-687.58.1.el9_8, kernel-rt-64k-5.14.0-687.58.1.el9_8, kernel-rt-64k-core-5.14.0-687.58.1.el9_8 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 9) kernel-rt-5.14.0-687.58.1.el9_8, kernel-rt-core-5.14.0-687.58.1.el9_8, kernel-rt-debug-5.14.0-687.58.1.el9_8 +9
Show 2 more Red Hat advisories
  • RHSA-2026:83157 Released 2026-10-14 · Red Hat rating Important
    kernel security, bug fix, and enhancement update
    • Red Hat Enterprise Linux BaseOS (v. 8) bpftool-4.18.0-553.174.1.el8_10, kernel-4.18.0-553.174.1.el8_10, kernel-abi-stablelists-4.18.0-553.174.1.el8_10 +19
    • Red Hat Enterprise Linux CRB (v. 8) kernel-tools-libs-devel-4.18.0-553.174.1.el8_10
  • RHSA-2026:83159 Released 2026-10-14 · Red Hat rating Important
    kernel-rt security, bug fix, and enhancement update
    • Red Hat Enterprise Linux NFV (v. 8) kernel-rt-4.18.0-553.174.1.rt7.515.el8_10, kernel-rt-core-4.18.0-553.174.1.rt7.515.el8_10, kernel-rt-debug-4.18.0-553.174.1.rt7.515.el8_10 +9
    • Red Hat Enterprise Linux RT (v. 8) kernel-rt-4.18.0-553.174.1.rt7.515.el8_10, kernel-rt-core-4.18.0-553.174.1.rt7.515.el8_10, kernel-rt-debug-4.18.0-553.174.1.rt7.515.el8_10 +7

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux 6Affected—
Red Hat Enterprise Linux 7AffectedNo fix yet
Red Hat Enterprise Linux 9AffectedNo fix yet
Red Hat OpenShift Container Platform 4AffectedNo fix yet
Red Hat OpenShift Container Platform 5AffectedNo fix yet
10Base-SMTVFixed RHSA-2026:83207
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2026:83207
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2026:83156
Red Hat Enterprise Linux BaseOS (v. 10)Fixed RHSA-2026:83207
Red Hat Enterprise Linux BaseOS (v. 8)Fixed RHSA-2026:83157
Red Hat Enterprise Linux BaseOS (v. 9)Fixed RHSA-2026:83156
Red Hat Enterprise Linux CRB (v. 8)Fixed RHSA-2026:83157
Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)Fixed RHSA-2026:83207
Red Hat Enterprise Linux CodeReady Linux Builder (v. 9)Fixed RHSA-2026:83156
Red Hat Enterprise Linux Hidden (v. 10)Fixed RHSA-2026:83207
Red Hat Enterprise Linux NFV (v. 8)Fixed RHSA-2026:83159
Red Hat Enterprise Linux RT (v. 8)Fixed RHSA-2026:83159
Red Hat Enterprise Linux Real Time (v. 10)Fixed RHSA-2026:83207
Red Hat Enterprise Linux Real Time (v. 9)Fixed RHSA-2026:83156
Red Hat Enterprise Linux Real Time for NFV (v. 10)Fixed RHSA-2026:83207
Red Hat Enterprise Linux Real Time for NFV (v. 9)Fixed RHSA-2026:83156
Red Hat OpenShift Container Platform 4.22Fixed RHSA-2026:89197

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-90036
  2. 2026-10-03 Alias added: GHSA-j6h5-vv56-hq58
  3. 2026-10-07 Affected versions changed · Red Hat
  4. 2026-10-07 CVSS score added · Red Hat
  5. 2026-10-16 Fix available: RHSA-2026:83159 · Red Hat
  6. 2026-10-16 Fix available: RHSA-2026:83156 · Red Hat
  7. 2026-10-16 Fix available: RHSA-2026:83157 · Red Hat
  8. 2026-10-16 Fix available: RHSA-2026:83207 · Red Hat
  9. 2026-10-16 Fix available: 10Base-SMTV, Red Hat Enterprise Linux AppStream (v. 10), Red Hat Enterprise Linux AppStream (v. 9) +13 · Red Hat
  10. 2026-10-19 Fix available: Linux/[email protected] · CNA
  11. 2026-10-21 Fix available: Linux/Linux@0d53a47c913d0bce3b5ec35c28cbcca4d015f33d, Linux/[email protected] · CNA
  12. 2026-10-21 1 new reference · CNA
  13. 2026-10-25 CVSS score changed · Red Hat
  14. 2026-10-28 Fix available: Red Hat OpenShift Container Platform 4.22 · Red Hat
  15. 2026-10-29 Fix available: RHSA-2026:89197 · Red Hat
  16. 2026-10-30 Affected versions changed · Red Hat

References

Other 5

  • 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