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TI-2026-60702 Aliases CVE-2026-89659GHSA-vgf3-w23r-qhq2

NFSD: Prevent client use-after-free during delegation revoke

Priority MEDIUM 49Published · 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: 4 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 delegation revoke A delegation stateid holds only a bare pointer to its owning nfs4_client and does not keep it alive. The client survives its stateids only because __destroy_client() drains cl_delegations and cl_revoked before free_client() runs. nfs4_laundromat() breaks that invariant: it unhashes an expired delegation from cl_delegations, drops deleg_lock, then revoke_delegation() relinks it onto cl_revoked under cl_lock. In that window the delegation is on neither list, so client_has_state() can report no remaining state. Every teardown path first requires cl_rpc_users to be zero, but the laundromat holds no such reference. A client whose recalled delegation has just timed out can therefore reach free_client() while revoke_delegation() is still about to dereference cl_lock, a use-after-free. Pin the client with cl_rpc_users across the revoke so teardown blocks until it completes, then reap the delegation from cl_revoked. A client already expiring reaps its own, so skip it and leave the delegation on del_recall_lru.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00477 41st percentileScored 2026-11-07
Fix Partial Linux (Linux): 6.1.191, 6.6.160, 6.12.111 +3Red Hat: 4 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux3.10 and later6.1.191, 6.6.160, 6.12.111, 6.18.51, 7.2.4, 7.3Patch availableCNA
  • Linux VendorLinux Affected 3.10 and later Fixed in 6.1.191, 6.6.160, 6.12.111, 6.18.51, 7.2.4, 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 6.1.191, 6.6.160, 6.12.111, 6.18.51, 7.2.4, 7.3

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux 10AffectedNo fix yet
Red Hat Enterprise Linux 7AffectedNo fix yet
Red Hat Enterprise Linux 8AffectedNo fix yet
Red Hat Enterprise Linux 9AffectedNo fix yet
Not affected: 1 product
  • Red Hat Enterprise Linux 6

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-89659
  2. 2026-10-03 Alias added: GHSA-vgf3-w23r-qhq2
  3. 2026-10-18 CISA SSVC decision points changed
  4. 2026-10-19 Fix available: Linux/[email protected] · CNA
  5. 2026-10-21 Fix available: Linux/[email protected], Linux/Linux@94f0c73797c30a35812ffb32d11b8737d245c405 · CNA
  6. 2026-10-21 1 new reference · CNA
  7. 2026-10-30 Affected versions changed · Red Hat
  8. 2026-10-30 Fix available: Linux/Linux@2f9a200c0ea5b214609b8cea2b6666458bcb54cd, Linux/[email protected] · CNA
  9. 2026-10-30 1 new reference · CNA
  10. 2026-11-01 Affected versions changed · Red Hat
  11. 2026-11-01 CVSS score changed · Red Hat

References

Other 6

  • 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