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TI-2026-68062 Aliases CVE-2026-98171GHSA-68gh-wq6f-89rf

Use-after-free in Linux kernel SMB client compound PDU handling

Priority LOW 39Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
Required
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 5 without a fix

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat.

Summary

The Linux kernel SMB client is affected from 4.19 before the fixed version of each stable branch. In receive_encrypted_standard(), compound encrypted frames are handled with a stale next_buffer pointer, the pre-decryption length, and an insufficient check of the NextCommand offset, including an integer overflow in the upper bound check. A remote attacker without privileges can affect confidentiality, integrity and availability, but user interaction is required.

Written with Claude Haiku 5.5 from the sources below · 2026-11-02

Description from the CNA

In the Linux kernel, the following vulnerability has been resolved: smb: client: fix next_buffer UAF and NextCommand bounds in compound PDUs Fix several related bounds checking and pointer lifecycle issues in receive_encrypted_standard()'s handling of compound encrypted frames: - Clear next_buffer after assigning it to server->bigbuf. A stale next_buffer pointer can lead to a use-after-free on subsequent error paths. - Update pdu_length to the decrypted plaintext size (buf_size). Using the pre-decryption length allows NextCommand to point into stale ciphertext residue. - Reject next_cmd values smaller than MID_HEADER_SIZE(server). - Fix an integer overflow in the upper bound check by verifying pdu_length - next_cmd < MID_HEADER_SIZE(server), ensuring the trailing slice is large enough for a header.

Why it matters now

EPSS 0.00537 45th 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
LinuxLinux4.19 and later5.10.273, 5.15.224, 6.1.189, 6.6.158, 6.12.112, 6.18.54, 7.2.8, 7.3Patch availableCNA
  • Linux VendorLinux Affected 4.19 and later Fixed in 5.10.273, 5.15.224, 6.1.189, 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

Update the Linux kernel to 5.10.273, 5.15.224, 6.1.189, 6.6.158, 6.12.112, 6.18.54, 7.2.8 or 7.3 for the matching stable branch. Red Hat lists Red Hat Enterprise Linux 8, 9 and 10 and Red Hat OpenShift Container Platform 4 and 5 as affected, with a plan of none available.

Written with Claude Haiku 5.5 from the sources below · 2026-11-02

  • Fix · CNA Linux (Linux) Fixed in 5.10.273, 5.15.224, 6.1.189, 6.6.158, 6.12.112, 6.18.54, 7.2.8, 7.3

Vendor assessments

Red Hat

Red Hat rating: Important. 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. 2026-10-06 Threatist record created from CVE-2026-98171
  2. 2026-10-06 Alias added: GHSA-68gh-wq6f-89rf
  3. 2026-10-07 CVSS score added · CNA
  4. 2026-10-19 Fix available: Linux/[email protected] · CNA
  5. 2026-10-30 Fix available: Linux/Linux@1ed29f7a03417b405f38c09cfe04124883127b53, Linux/[email protected], Linux/[email protected] +1 · CNA
  6. 2026-10-30 2 new references · CNA
  7. 2026-11-02 Affected versions changed · Red Hat
  8. 2026-11-02 CVSS score added · Red Hat

References

Other 8

  • 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