Read the docs
TI-2026-68152 Aliases CVE-2026-98261GHSA-mfc9-mfpp-wwcf

Use-after-free in Linux kernel CIFS secondary channel handling

Priority LOW 35Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
High
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

The Linux kernel CIFS client is affected from 6.6.15 before 6.6.158, from 6.7.3 before 6.8, and from 6.8. When a secondary channel is no longer supported by the server, cifs_chan_skip_or_disable() drops a channel reference and then uses the freed channel and primary server. The CVSS 3.1 vector rates it remotely exploitable without privileges or user interaction, with high attack complexity.

Written with Claude Haiku 5.5 from the sources below · 2026-11-04

Description from the CNA

In the Linux kernel, the following vulnerability has been resolved: cifs: Fix server use-after-free in cifs_chan_skip_or_disable() When a secondary channel is no longer supported by the server, cifs_chan_skip_or_disable() drops the channel reference with cifs_put_tcp_session() and then continues to use the server pointer by calling cifs_signal_cifsd_for_reconnect() on it and reading its primary_server pointer. cifs_put_tcp_session() can drop the last reference of the channel and tear it down, so both the channel and the primary server (whose reference is also dropped by cifs_put_tcp_session()) can be freed before they are signaled for reconnect. Signal the channel and the primary server and capture the primary server pointer before dropping the channel reference with cifs_put_tcp_session().

Why it matters now

EPSS 0.00405 35th percentileScored 2026-11-07
Fix Partial Linux (Linux): 6.6.158, 6.8, 6.12.112 +3Red Hat: 4 without a fix

SSVC decision points

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

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux6.6.15 to before 6.6.158; 6.7.3 to before 6.86.6.158, 6.8Patch availableCNA
LinuxLinux6.8 and later6.6.158, 6.12.112, 6.18.54, 7.2.8, 7.3Patch availableCNA
  • Linux VendorLinux Affected 6.6.15 to before 6.6.158; 6.7.3 to before 6.8 Fixed in 6.6.158, 6.8 Patch available CNA
  • Linux VendorLinux Affected 6.8 and later Fixed in 6.6.158, 6.12.112, 6.18.54, 7.2.8, 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

Fixed Linux kernel versions are 6.6.158, 6.8, 6.12.112, 6.18.54, 7.2.8 and 7.3. The sources list no fixed version for Red Hat Enterprise Linux 9, Red Hat Enterprise Linux 10, Red Hat OpenShift Container Platform 4 or Red Hat OpenShift Container Platform 5.

Written with Claude Haiku 5.5 from the sources below · 2026-11-04

  • Fix · CNA Linux (Linux) Fixed in 6.6.158, 6.8
  • Fix · CNA Linux (Linux) Fixed in 6.6.158, 6.12.112, 6.18.54, 7.2.8, 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
Red Hat Enterprise Linux 9AffectedNo fix yet
Red Hat OpenShift Container Platform 4AffectedNo fix yet
Red Hat OpenShift Container Platform 5AffectedNo fix yet
Not affected: 5 products
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux 8
  • Red Hat Enterprise Linux 9
  • Red Hat OpenShift Container Platform 4

Timeline

  1. 2026-10-06 Threatist record created from CVE-2026-98261
  2. 2026-10-06 Alias added: GHSA-mfc9-mfpp-wwcf
  3. 2026-10-07 CVSS score added · CNA
  4. 2026-10-11 Affected versions changed · Red Hat
  5. 2026-10-11 CVSS score added · Red Hat
  6. 2026-10-19 Fix available: Linux/[email protected] · CNA
  7. 2026-10-27 CVSS score changed · Red Hat
  8. 2026-11-04 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