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TI-2026-61196 Aliases CVE-2026-90153GHSA-wffx-7972-vw67

ksmbd: bound smb_check_perm_dacl() ACE walks by DACL size

Priority LOW 36Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
High · High · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA.

Summary

In the Linux kernel, the following vulnerability has been resolved: ksmbd: bound smb_check_perm_dacl() ACE walks by DACL size smb_check_perm_dacl() validates that the DACL fits inside the NT security descriptor, but then bounds its two ACE walks by the remaining NTSD length (acl_size) rather than the DACL's declared size (pdacl_size). When pdacl->size is smaller than the trailing NTSD buffer, bytes after the declared DACL boundary - still inside the stored security descriptor - are parsed as ACEs during access checks. A crafted DACL can place an access-granting ACE beyond pdacl->size, and the current code accepts it during SMB2_CREATE access validation, while parse_dacl() and smb_inherit_dacl() stop at pdacl_size. Bound both ACE walks by pdacl_size to match the DACL boundary semantics used elsewhere in the server. Validation: - semantic KUnit harness shows the post-boundary ACE is selected before the fix and rejected (EACCES) after it - linux master (7.2-rc6), x86_64

Why it matters now

EPSS 0.00522 44th percentileScored 2026-11-07
Fix Fixed Linux (Linux): 5.16, 5.19, 5.20 +6

SSVC decision points

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

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux5.15.62 to before 5.16; 5.18.18 to before 5.19; 5.19.2 to before 5.205.16, 5.19, 5.20Patch availableCNA
LinuxLinux6.0 and later6.1.191, 6.6.157, 6.12.110, 6.18.52, 7.2.6, 7.3Patch availableCNA
  • Linux VendorLinux Affected 5.15.62 to before 5.16; 5.18.18 to before 5.19; 5.19.2 to before 5.20 Fixed in 5.16, 5.19, 5.20 Patch available CNA
  • Linux VendorLinux Affected 6.0 and later Fixed in 6.1.191, 6.6.157, 6.12.110, 6.18.52, 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 5.16, 5.19, 5.20
  • Fix · CNA Linux (Linux) Fixed in 6.1.191, 6.6.157, 6.12.110, 6.18.52, 7.2.6, 7.3

Vendor assessments

Red Hat

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

Not affected: 7 products
  • Red Hat Enterprise Linux 10
  • 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
  • Red Hat OpenShift Container Platform 5

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-90153
  2. 2026-10-03 Alias added: GHSA-wffx-7972-vw67
  3. 2026-10-19 Fix available: Linux/[email protected] · CNA
  4. 2026-10-21 Affected versions changed · Red Hat
  5. 2026-10-21 CVSS score added · Red Hat
  6. 2026-10-30 Fix available: Linux/[email protected], Linux/Linux@930dcdd888eabf166589e020dcbf6d15b5e13305 · CNA
  7. 2026-10-30 1 new reference · CNA
  8. 2026-10-30 Affected versions changed · Red Hat

References

Other 6

  • 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