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TI-2026-61276 Aliases CVE-2026-90234GHSA-qx9f-2gch-8fvp

NFS: Return a delegation the client fails to record

Priority LOW 34Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 7 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: NFS: Return a delegation the client fails to record When an NFS server grants a delegation in an OPEN reply, nfs_inode_set_delegation() records it on the client. However, three of its error flows return without sending DELEGRETURN. A delegation can be relinquished only by DELEGRETURN (RFC 8881 Section 20.2.4), so dropping one silently leaves the server believing the client still holds it. If the server happens to recall that delegation, the client answers CB_RECALL with NFS4ERR_BADHANDLE because it has no record of the stateid. The server revokes the delegation and moves it onto its cl_revoked list, because the client never sends the FREE_STATEID that would drain it. Every subsequent SEQUENCE reply then carries SEQ4_STATUS_RECALLABLE_STATE_REVOKED, and the client's state manager loops issuing TEST_STATEID across its delegations without ever clearing the condition. The window is easy to reach now that a server offers a write delegation on any write OPEN: a delegation recalled for one opener races a re-open that the server answers with a fresh write delegation. Instead of dropping it, hand the delegation back during these error flows.

Why it matters now

EPSS 0.00684 52nd percentileScored 2026-11-07
Fix Partial Linux (Linux): 6.1.191, 6.6.160, 6.12.114 +3Red Hat: 7 without a fix

SSVC decision points

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

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux4.0 and later6.1.191, 6.6.160, 6.12.114, 6.18.57, 7.2.6, 7.3Patch availableCNA
  • Linux VendorLinux Affected 4.0 and later Fixed in 6.1.191, 6.6.160, 6.12.114, 6.18.57, 7.2.6, 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, 6.12.114, 6.18.57, 7.2.6, 7.3

Vendor assessments

Red Hat

Red Hat rating: Moderate. 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 7AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 8AffectedNo fix yet: Fix deferred
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

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-90234
  2. 2026-10-03 Alias added: GHSA-qx9f-2gch-8fvp
  3. 2026-10-15 Affected versions changed · Red Hat
  4. 2026-10-15 CVSS score added · Red Hat
  5. 2026-10-16 Fix available: Linux/[email protected], Linux/Linux@6822ba1ae9b6df6a094f7f8998f1da734c85fa19 · CNA
  6. 2026-10-16 1 new reference · CNA
  7. 2026-10-19 Fix available: Linux/[email protected] · CNA
  8. 2026-10-21 Affected versions changed · Red Hat
  9. 2026-10-21 CVSS score changed · Red Hat
  10. 2026-10-21 Fix available: Linux/[email protected], Linux/[email protected], Linux/Linux@9e71e332fa2c7a48f3d00001f856a13cc2d69639 +1 · CNA
  11. 2026-10-21 2 new references · CNA
  12. 2026-10-28 EPSS moved to the 50th–90th percentile
  13. 2026-10-30 Fix available: Linux/[email protected], Linux/Linux@61b23f482b2082e77d2f78bd1624f93a12ec35ce · CNA
  14. 2026-10-30 1 new reference · CNA
  15. 2026-10-30 Affected versions changed · Red Hat

References

  • 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