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TI-2025-15747 Aliases CVE-2025-21795GHSA-v47h-hxgq-326f

NFSD: fix hang in nfsd4_shutdown_callback

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: 15 fixed, 2 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: fix hang in nfsd4_shutdown_callback If nfs4_client is in courtesy state then there is no point to send the callback. This causes nfsd4_shutdown_callback to hang since cl_cb_inflight is not 0. This hang lasts about 15 minutes until TCP notifies NFSD that the connection was dropped. This patch modifies nfsd4_run_cb_work to skip the RPC call if nfs4_client is in courtesy state.

Why it matters now

EPSS 0.00668 52nd percentileScored 2026-11-07
Fix Partial Linux (Linux): 5.10.235, 5.15.179, 6.1.129 +4Red Hat: 3 advisoriesRed Hat: 15 fixed, 2 without a fix

SSVC decision points

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

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux5.10.220 to before 5.10.235; 5.15.154 to before 5.15.1795.10.235, 5.15.179Patch availableCNA
LinuxLinux5.19 and later5.10.235, 5.15.179, 6.1.129, 6.6.79, 6.12.16, 6.13.4, 6.14Patch availableCNA
  • Linux VendorLinux Affected 5.10.220 to before 5.10.235; 5.15.154 to before 5.15.179 Fixed in 5.10.235, 5.15.179 Patch available CNA
  • Linux VendorLinux Affected 5.19 and later Fixed in 5.10.235, 5.15.179, 6.1.129, 6.6.79, 6.12.16, 6.13.4, 6.14 Patch available CNA

CPE configurations NVD · 3

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*5.10.220 to before 5.10.235; 5.15.154 to before 5.15.179; 5.19 to before 6.1.129; 6.2 to before 6.6.79; 6.7 to before 6.12.16; 6.13 to before 6.13.4VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.14:rc1:*:*:*:*:*:*6.14 rc1VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.14:rc2:*:*:*:*:*:*6.14 rc2VulnerableLinux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 5.10.220 to before 5.10.235; 5.15.154 to before 5.15.179; 5.19 to before 6.1.129; 6.2 to before 6.6.79; 6.7 to before 6.12.16; 6.13 to before 6.13.4 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.14:rc1:*:*:*:*:*:* Versions 6.14 rc1 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.14:rc2:*:*:*:*:*:* Versions 6.14 rc2 Vulnerable ·Linux

Remediation

  • Fix · CNA Linux (Linux) Fixed in 5.10.235, 5.15.179
  • Fix · CNA Linux (Linux) Fixed in 5.10.235, 5.15.179, 6.1.129, 6.6.79, 6.12.16, 6.13.4, 6.14

Red Hat 3 advisories

  • RHSA-2026:0804 Released 2026-01-19 · Red Hat rating Important
    kernel security update
    • Red Hat CodeReady Linux Builder EUS (v.9.6) kernel-tools-libs-devel-5.14.0-570.79.1.el9_6, libperf-5.14.0-570.79.1.el9_6
    • Red Hat Enterprise Linux AppStream EUS (v.9.6) kernel-64k-debug-devel-5.14.0-570.79.1.el9_6, kernel-64k-debug-devel-matched-5.14.0-570.79.1.el9_6, kernel-64k-devel-5.14.0-570.79.1.el9_6 +12
    • Red Hat Enterprise Linux BaseOS EUS (v.9.6) kernel-5.14.0-570.79.1.el9_6, kernel-64k-5.14.0-570.79.1.el9_6, kernel-64k-core-5.14.0-570.79.1.el9_6 +28
    • Red Hat Enterprise Linux Real Time EUS (v.9.6) kernel-rt-5.14.0-570.79.1.el9_6, kernel-rt-64k-5.14.0-570.79.1.el9_6, kernel-rt-64k-core-5.14.0-570.79.1.el9_6 +21
    • Red Hat Enterprise Linux Real Time for NFV EUS (v.9.6) kernel-rt-5.14.0-570.79.1.el9_6, kernel-rt-core-5.14.0-570.79.1.el9_6, kernel-rt-debug-5.14.0-570.79.1.el9_6 +11
  • RHSA-2025:20518 Released 2025-11-11 · Red Hat rating Moderate
    kernel security update
    • Red Hat Enterprise Linux AppStream (v. 9) kernel-64k-debug-devel-5.14.0-611.5.1.el9_7, kernel-64k-debug-devel-matched-5.14.0-611.5.1.el9_7, kernel-64k-devel-5.14.0-611.5.1.el9_7 +12
    • Red Hat Enterprise Linux BaseOS (v. 9) kernel-5.14.0-611.5.1.el9_7, kernel-64k-5.14.0-611.5.1.el9_7, kernel-64k-core-5.14.0-611.5.1.el9_7 +28
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) kernel-tools-libs-devel-5.14.0-611.5.1.el9_7, libperf-5.14.0-611.5.1.el9_7
    • Red Hat Enterprise Linux Real Time (v. 9) kernel-rt-5.14.0-611.5.1.el9_7, kernel-rt-64k-5.14.0-611.5.1.el9_7, kernel-rt-64k-core-5.14.0-611.5.1.el9_7 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 9) kernel-rt-5.14.0-611.5.1.el9_7, kernel-rt-core-5.14.0-611.5.1.el9_7, kernel-rt-debug-5.14.0-611.5.1.el9_7 +9
  • RHSA-2025:20095 Released 2025-11-11 · Red Hat rating Moderate
    kernel security update
    • Red Hat Enterprise Linux AppStream (v. 10) kernel-64k-debug-devel-6.12.0-124.8.1.el10_1, kernel-64k-debug-devel-matched-6.12.0-124.8.1.el10_1, kernel-64k-devel-6.12.0-124.8.1.el10_1 +12
    • Red Hat Enterprise Linux BaseOS (v. 10) kernel-6.12.0-124.8.1.el10_1, kernel-64k-6.12.0-124.8.1.el10_1, kernel-64k-core-6.12.0-124.8.1.el10_1 +29
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) kernel-tools-libs-devel-6.12.0-124.8.1.el10_1, libperf-6.12.0-124.8.1.el10_1
    • Red Hat Enterprise Linux Real Time (v. 10) kernel-rt-6.12.0-124.8.1.el10_1, kernel-rt-64k-6.12.0-124.8.1.el10_1, kernel-rt-64k-core-6.12.0-124.8.1.el10_1 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 10) kernel-rt-6.12.0-124.8.1.el10_1, kernel-rt-core-6.12.0-124.8.1.el10_1, kernel-rt-debug-6.12.0-124.8.1.el10_1 +9

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux 6AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 7AffectedNo fix planned: Out of support scope
Red Hat CodeReady Linux Builder EUS (v.9.6)Fixed RHSA-2026:0804
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2025:20095
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2025:20518
Red Hat Enterprise Linux AppStream EUS (v.9.6)Fixed RHSA-2026:0804
Red Hat Enterprise Linux BaseOS (v. 10)Fixed RHSA-2025:20095
Red Hat Enterprise Linux BaseOS (v. 9)Fixed RHSA-2025:20518
Red Hat Enterprise Linux BaseOS EUS (v.9.6)Fixed RHSA-2026:0804
Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)Fixed RHSA-2025:20095
Red Hat Enterprise Linux CodeReady Linux Builder (v. 9)Fixed RHSA-2025:20518
Red Hat Enterprise Linux Real Time (v. 10)Fixed RHSA-2025:20095
Red Hat Enterprise Linux Real Time (v. 9)Fixed RHSA-2025:20518
Red Hat Enterprise Linux Real Time EUS (v.9.6)Fixed RHSA-2026:0804
Red Hat Enterprise Linux Real Time for NFV (v. 10)Fixed RHSA-2025:20095
Red Hat Enterprise Linux Real Time for NFV (v. 9)Fixed RHSA-2025:20518
Red Hat Enterprise Linux Real Time for NFV EUS (v.9.6)Fixed RHSA-2026:0804
Not affected: 1 product
  • Red Hat Enterprise Linux 8

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-21795
  2. 2026-10-03 Alias added: GHSA-v47h-hxgq-326f
  3. 2026-10-16 EPSS moved to the 50th–90th percentile
  4. 2026-10-29 Affected versions changed · Red Hat

References

Patch 7

  • 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-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
  • TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
See all 15278 →

Sources

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