CVE-2026-98318
Received
Received - Intake
Linux Kernel SMB Client Symlink Target Validation Flaw
Vulnerability report for CVE-2026-98318, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-10-06
Last updated on: 2026-10-06
Assigner: kernel.org
Description
Description
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.
CVSS Scores
EPSS Scores
| Probability: | |
| Percentile: |
Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| Linux | Linux | 3363da82e02f1bddc54faa92ea430c6532e2cd2e |
| Linux | Linux | 3363da82e02f1bddc54faa92ea430c6532e2cd2e |
| Linux | Linux | b6ea7b6c6be65149ab6b8e37a9dd1671f76add1b |
| Linux | Linux | 6.15.6 |
| Linux | Linux | 6.16 |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-UNKNOWN |
