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TI-2026-64194 Aliases CVE-2026-97564GHSA-3fc8-28wq-wq67

smb: client: reject userspace cifs.idmap descriptions

Priority LOW 22Published · Updated

Key facts

Attack vector
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Privileges required
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User interaction
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Attack complexity
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Impact type
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Confidentiality · integrity · availability
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Fix status
Partial Red Hat: 5 without a fix

No CVSS vector from any source. Fix status from CNA and Red Hat.

Summary

In the Linux kernel, the following vulnerability has been resolved: smb: client: reject userspace cifs.idmap descriptions cifs.idmap key descriptions carry authority-bearing fields (owner and group SIDs and uid/gid values in "os:"/"gs:"/"oi:"/"gi:" form) that the cifs.idmap upcall helper treats as kernel-originating inputs. Unlike its sibling cifs.spnego, the cifs.idmap key type has no vet_description hook, so userspace can create keys of this type through request_key(2)/add_key(2) and supply those fields without CIFS origin. A request_key(2) call with a non-NULL callout then drives a root usermodehelper upcall (/sbin/request-key -> cifs.idmap) that consumes the unvetted description in root context. Only accept cifs.idmap descriptions while CIFS is using its private root_cred to request the key. id_to_sid()/sid_to_id() already run under override_creds(root_cred), so the kernel-originated path is unaffected. This mirrors commit 3da1fdf4efbc ("smb: client: reject userspace cifs.spnego descriptions"), which applied the same restriction to cifs.spnego.

Why it matters now

EPSS 0.00216 12th percentileScored 2026-11-07
Fix Partial Linux (Linux): 5.10.273, 5.15.224, 6.1.189 +5Red Hat: 5 without a fix

SSVC decision points

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

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux3.0 and later5.10.273, 5.15.224, 6.1.189, 6.6.158, 6.12.111, 6.18.53, 7.2.7, 7.3Patch availableCNA
  • Linux VendorLinux Affected 3.0 and later Fixed in 5.10.273, 5.15.224, 6.1.189, 6.6.158, 6.12.111, 6.18.53, 7.2.7, 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 5.10.273, 5.15.224, 6.1.189, 6.6.158, 6.12.111, 6.18.53, 7.2.7, 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 8AffectedNo 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: 2 products
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-97564
  2. 2026-10-03 Alias added: GHSA-3fc8-28wq-wq67
  3. 2026-10-03 Fix available: Linux/Linux@17c93bcd17755523c21abb22cbf2a41a6eb0caaf, Linux/[email protected], Linux/[email protected] +1 · CNA
  4. 2026-10-03 2 new references · CNA
  5. 2026-10-19 Fix available: Linux/[email protected] · CNA
  6. 2026-10-30 Affected versions changed · Red Hat
  7. 2026-10-30 Fix available: Linux/[email protected], Linux/[email protected], Linux/Linux@856cb3f05b49d23dc1542f78696e20c4ea6dd7de +1 · CNA
  8. 2026-10-30 2 new references · CNA

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-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