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TI-2026-45701 Aliases CVE-2026-64136GHSA-6vvf-f9vp-vcgv

smb: client: protect tc_count increment in smb2_find_smb_sess_tcon_unlocked()

Priority MEDIUM 49CWE-362Published · 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
Fixed

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: smb: client: protect tc_count increment in smb2_find_smb_sess_tcon_unlocked() Commit 96c4af418586 ("cifs: Fix locking usage for tcon fields") refactored cifs code to change cifs_tcp_ses_lock for tc_lock around tc_count changes. There was missing lock around tc_count increment inside smb2_find_smb_sess_tcon_unlocked().

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00407 35th percentileScored 2026-11-07
Fix Fixed Linux (Linux): 6.6.142, 6.12.92, 6.18.34 +3Red Hat: 2 advisories

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
LinuxLinux6.6.128 to before 6.6.142; 6.12.75 to before 6.12.92; 6.18.16 to before 6.18.34; 6.19.6 to before 6.206.6.142, 6.12.92, 6.18.34, 6.20Patch availableCNA
LinuxLinux7.0 and later6.6.142, 6.12.92, 6.18.34, 7.0.11, 7.1Patch availableCNA
  • Linux VendorLinux Affected 6.6.128 to before 6.6.142; 6.12.75 to before 6.12.92; 6.18.16 to before 6.18.34; 6.19.6 to before 6.20 Fixed in 6.6.142, 6.12.92, 6.18.34, 6.20 Patch available CNA
  • Linux VendorLinux Affected 7.0 and later Fixed in 6.6.142, 6.12.92, 6.18.34, 7.0.11, 7.1 Patch available CNA

CPE configurations NVD · 5

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*6.6.128 to before 6.6.142; 6.12.75 to before 6.12.92; 6.18.16 to before 6.18.34; 6.19.6 to before 7.0.11VulnerableLinux
cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:*7.1 rc1VulnerableLinux
cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:*7.1 rc2VulnerableLinux
cpe:2.3:o:linux:linux_kernel:7.1:rc3:*:*:*:*:*:*7.1 rc3VulnerableLinux
cpe:2.3:o:linux:linux_kernel:7.1:rc4:*:*:*:*:*:*7.1 rc4VulnerableLinux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 6.6.128 to before 6.6.142; 6.12.75 to before 6.12.92; 6.18.16 to before 6.18.34; 6.19.6 to before 7.0.11 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:* Versions 7.1 rc1 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:* Versions 7.1 rc2 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:7.1:rc3:*:*:*:*:*:* Versions 7.1 rc3 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:7.1:rc4:*:*:*:*:*:* Versions 7.1 rc4 Vulnerable ·Linux

Remediation

  • Fix · CNA Linux (Linux) Fixed in 6.6.142, 6.12.92, 6.18.34, 6.20
  • Fix · CNA Linux (Linux) Fixed in 6.6.142, 6.12.92, 6.18.34, 7.0.11, 7.1

Red Hat 2 advisories

  • RHSA-2026:64808 Released 2026-09-08 · Red Hat rating Important
    kernel security update
    • Red Hat Enterprise Linux AppStream (v. 9) kernel-64k-debug-devel-5.14.0-687.45.1.el9_8, kernel-64k-debug-devel-matched-5.14.0-687.45.1.el9_8, kernel-64k-devel-5.14.0-687.45.1.el9_8 +12
    • Red Hat Enterprise Linux BaseOS (v. 9) kernel-5.14.0-687.45.1.el9_8, kernel-64k-5.14.0-687.45.1.el9_8, kernel-64k-core-5.14.0-687.45.1.el9_8 +28
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) kernel-tools-libs-devel-5.14.0-687.45.1.el9_8, libperf-5.14.0-687.45.1.el9_8
    • Red Hat Enterprise Linux Real Time (v. 9) kernel-rt-5.14.0-687.45.1.el9_8, kernel-rt-64k-5.14.0-687.45.1.el9_8, kernel-rt-64k-core-5.14.0-687.45.1.el9_8 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 9) kernel-rt-5.14.0-687.45.1.el9_8, kernel-rt-core-5.14.0-687.45.1.el9_8, kernel-rt-debug-5.14.0-687.45.1.el9_8 +9
  • RHSA-2026:61887 Released 2026-09-01 · Red Hat rating Important
    kernel security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream (v. 10) kernel-64k-debug-devel-6.12.0-211.50.1.el10_2, kernel-64k-debug-devel-matched-6.12.0-211.50.1.el10_2, kernel-64k-devel-6.12.0-211.50.1.el10_2 +12
    • Red Hat Enterprise Linux BaseOS (v. 10) kernel-6.12.0-211.50.1.el10_2, kernel-64k-6.12.0-211.50.1.el10_2, kernel-64k-core-6.12.0-211.50.1.el10_2 +29
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) kernel-tools-libs-devel-6.12.0-211.50.1.el10_2, libperf-6.12.0-211.50.1.el10_2
    • Red Hat Enterprise Linux Real Time (v. 10) kernel-rt-6.12.0-211.50.1.el10_2, kernel-rt-64k-6.12.0-211.50.1.el10_2, kernel-rt-64k-core-6.12.0-211.50.1.el10_2 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 10) kernel-rt-6.12.0-211.50.1.el10_2, kernel-rt-core-6.12.0-211.50.1.el10_2, kernel-rt-debug-6.12.0-211.50.1.el10_2 +9

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2026:61887
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2026:64808
Red Hat Enterprise Linux BaseOS (v. 10)Fixed RHSA-2026:61887
Red Hat Enterprise Linux BaseOS (v. 9)Fixed RHSA-2026:64808
Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)Fixed RHSA-2026:61887
Red Hat Enterprise Linux CodeReady Linux Builder (v. 9)Fixed RHSA-2026:64808
Red Hat Enterprise Linux Real Time (v. 10)Fixed RHSA-2026:61887
Red Hat Enterprise Linux Real Time (v. 9)Fixed RHSA-2026:64808
Red Hat Enterprise Linux Real Time for NFV (v. 10)Fixed RHSA-2026:61887
Red Hat Enterprise Linux Real Time for NFV (v. 9)Fixed RHSA-2026:64808
Not affected: 4 products
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux 8
  • Red Hat Enterprise Linux 9

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-64136
  2. 2026-10-03 Alias added: GHSA-6vvf-f9vp-vcgv
  3. 2026-10-07 EPSS moved to the below the 50th percentile
  4. 2026-10-16 CISA SSVC decision points changed
  5. 2026-10-19 Weakness changed · CISA ADP
  6. 2026-10-29 Affected versions changed · Red Hat
  7. 2026-10-30 Fix available: Linux/Linux@7585d4242f59185b084957fa077396e53dbf7c24 · CNA
  8. 2026-10-30 1 new reference · CNA

References

Patch 5

Other 1

  • 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