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TI-2026-45592 Aliases CVE-2026-64027GHSA-p8c9-j99c-x8w3

net: shaper: rework the VALID marking (again)

Priority LOW 35CWE-362Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 7 fixed, 1 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: net: shaper: rework the VALID marking (again) Recent commit changed the semantics from NOT_VALID to VALID. I didn't realize that the flags are not stored atomically with the entry in XArray. There's still a race of reader observing a VALID mark for a slot, getting interrupted, writer replacing the entry with a different one, reader continuing, fetching the entry which is now a different pointer than the pointer for which VALID was meant. The biggest consequence of this is that we may see a UAF since net_shaper_rollback() assumed that entries without VALID can be freed without observing RCU. Looks like the XArray marks are buying us nothing at this point. Let's convert the code to an explicit valid field. The smp_load_acquire() / smp_store_release() barriers are marginally cleaner.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00099 0th percentileScored 2026-11-07
Fix Partial Linux (Linux): 6.18.34, 7.0.11, 7.1Red Hat: 1 advisoryRed Hat: 7 fixed, 1 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
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
LinuxLinux6.13 and later6.18.34, 7.0.11, 7.1Patch availableCNA
  • Linux VendorLinux Affected 6.13 and later Fixed in 6.18.34, 7.0.11, 7.1 Patch available CNA

CPE configurations NVD · 5

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*6.13 to before 6.18.34; 6.19 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 6.13 to before 6.18.34; 6.19 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 6.18.34, 7.0.11, 7.1

Red Hat 1 advisory

  • RHSA-2026:91565 Released 2026-10-28 · Red Hat rating Important
    kernel security, bug fix, and enhancement update
    • 10Base-SMTV kernel-modules-internal-6.12.0-211.69.1.el10_2
    • Red Hat Enterprise Linux AppStream (v. 10) kernel-64k-debug-devel-6.12.0-211.69.1.el10_2, kernel-64k-debug-devel-matched-6.12.0-211.69.1.el10_2, kernel-64k-devel-6.12.0-211.69.1.el10_2 +12
    • Red Hat Enterprise Linux BaseOS (v. 10) kernel-6.12.0-211.69.1.el10_2, kernel-64k-6.12.0-211.69.1.el10_2, kernel-64k-core-6.12.0-211.69.1.el10_2 +29
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) kernel-tools-libs-devel-6.12.0-211.69.1.el10_2, libperf-6.12.0-211.69.1.el10_2
    • Red Hat Enterprise Linux Hidden (v. 10) kernel-modules-internal-6.12.0-211.69.1.el10_2
    • Red Hat Enterprise Linux Real Time (v. 10) kernel-rt-6.12.0-211.69.1.el10_2, kernel-rt-64k-6.12.0-211.69.1.el10_2, kernel-rt-64k-core-6.12.0-211.69.1.el10_2 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 10) kernel-rt-6.12.0-211.69.1.el10_2, kernel-rt-core-6.12.0-211.69.1.el10_2, kernel-rt-debug-6.12.0-211.69.1.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 9AffectedNo fix yet
10Base-SMTVFixed RHSA-2026:91565
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2026:91565
Red Hat Enterprise Linux BaseOS (v. 10)Fixed RHSA-2026:91565
Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)Fixed RHSA-2026:91565
Red Hat Enterprise Linux Hidden (v. 10)Fixed RHSA-2026:91565
Red Hat Enterprise Linux Real Time (v. 10)Fixed RHSA-2026:91565
Red Hat Enterprise Linux Real Time for NFV (v. 10)Fixed RHSA-2026:91565
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-2026-64027
  2. 2026-10-03 Alias added: GHSA-p8c9-j99c-x8w3
  3. 2026-10-13 Affected versions changed · Red Hat
  4. 2026-10-13 Weakness changed · NVD
  5. 2026-10-16 CISA SSVC decision points changed
  6. 2026-10-19 Weakness changed · CISA ADP
  7. 2026-10-27 CVSS score changed · Red Hat
  8. 2026-10-29 Fix available: RHSA-2026:91565 · Red Hat
  9. 2026-10-29 Fix available: 10Base-SMTV, Red Hat Enterprise Linux AppStream (v. 10), Red Hat Enterprise Linux BaseOS (v. 10) +4 · 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-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