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TI-2026-68209 Aliases CVE-2026-98318GHSA-fp2w-r96h-w2cp

Linux kernel smb client overflow from unvalidated absolute symlink targets

Priority LOW 33Published · 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: 4 without a fix

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

Summary

With symlinkroot unset, the SMB client copies an absolute symlink target to an NT drive path without conversion, but later code still assumes an NT prefix is present. For the target "/ab", sym[5] and path[5] are written past their allocations, and subtracting an assumed 8-byte prefix from a 6-byte UTF-16 target wraps plen to 65534, so memcpy() copies 65534 bytes into a 24-byte buffer. A user with write access to a mounted share can trigger these bugs with default settings. CVSS 3.1 scores it 7.8 (HIGH), and Red Hat rates it Important.

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

Description from the CNA

In the Linux kernel, the following vulnerability has been resolved: smb: client: validate absolute native symlink targets before NT fixups With symlinkroot unset, an absolute target is copied without conversion to an NT drive path. Later code still assumes an NT prefix is present when modifying the target and calculating the print name length. For "/ab", this causes two failures: sym[5] and path[5] are written past their allocations, and plen -= 2 * poff subtracts an assumed 8-byte prefix from a 6-byte UTF-16 target, wrapping u16 plen to 65534. That underflow causes another overflow: memcpy() copies 65534 bytes into a 24-byte buffer. A user with write access to a mounted share can trigger these bugs with default settings. Validate the NT drive prefix, including an ASCII drive letter, before accessing fixed offsets or subtracting the prefix length.

Why it matters now

EPSS 0.0012 1st percentileScored 2026-11-07
Fix Partial Linux (Linux): 6.16, 7.2.8, 7.3Red Hat: 4 without a fix

SSVC decision points

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

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux6.15.6 to before 6.166.16Patch availableCNA
LinuxLinux6.16 and later7.2.8, 7.3Patch availableCNA
  • Linux VendorLinux Affected 6.15.6 to before 6.16 Fixed in 6.16 Patch available CNA
  • Linux VendorLinux Affected 6.16 and later Fixed in 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 to Linux kernel 6.16 if you run the 6.15.6 line, or to 7.2.8 or 7.3 if you run 6.16 or later. Red Hat reports no fix plan yet for Red Hat Enterprise Linux 9 and 10 and Red Hat OpenShift Container Platform 4 and 5.

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

  • Fix · CNA Linux (Linux) Fixed in 6.16
  • Fix · CNA Linux (Linux) Fixed in 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 9AffectedNo fix yet
Red Hat OpenShift Container Platform 4AffectedNo fix yet
Red Hat OpenShift Container Platform 5AffectedNo fix yet
Not affected: 5 products
  • 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

Timeline

  1. 2026-10-06 Threatist record created from CVE-2026-98318
  2. 2026-10-06 Alias added: GHSA-fp2w-r96h-w2cp
  3. 2026-10-07 CVSS score added · CNA
  4. 2026-10-10 Affected versions changed · Red Hat
  5. 2026-10-10 CVSS score added · Red Hat
  6. 2026-10-19 Fix available: Linux/[email protected] · CNA
  7. 2026-10-30 Affected versions changed · Red Hat

References

Other 2

  • 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 21727 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences