CVE-2026-98454

What it is

In the Linux kernel, the following vulnerability has been resolved: smb: client: fix create context out-of-bounds reads smb2_parse_contexts() validates the complete create-context area but does not limit each record to its Next field before dispatching it. A malformed chain can therefore expose bytes beyond the current context to a handler. The QFid handler also used a full response-structure cast although it only reads DiskFileId. The SMB2/SMB3 lease parsers made the same layout assumption: they read LeaseState and LeaseFlags at canonical offsets rather than at DataOffset. A valid non-canonical DataOffset could therefore yield unrelated in-bounds data, while a short DataLength was still accepted. Limit each context to its Next value, reject offsets before the context header, and reject malformed chains. Bound the name range by the current context and do not dispatch a known handler when DataLength is zero. Read the QFid DiskFileId only when the context data covers that field. Parse the lease context from DataOffset and require DataLength to match the v1 or v2 lease_context size used by ksmbd. A size mismatch skips lease parsing without failing the open.

At a glance

Exploitability

Can be exploited over the network without logging in, but needs a user to act. High risk of data exposure, service disruption.

Exploit odds

0.4% chance of exploitation in the next 30 days (EPSS).

Fix

No patch or advisory is linked yet. Look at mitigations or restrict exposure.

Timeline

1. 2026-09-25 10:25 UTC ReservedThe CVE id was reserved by its CNA
2. 2026-10-18 16:16 UTC PublishedDisclosed publicly on CVE.org and NVD
3. 2026-10-30 13:21 UTC Last updatedMost recent change to the record

Why it ranks here

• Exploited in the wild: no, CISA does not list it.
• Exploit odds: 0.4% in the next 30 days (EPSS).
• Severity: 8.1 HIGH (CVSS).
• Fix: none linked yet, which raises it.

Details

Published

2026-10-18 16:16 UTC

Last modified

2026-10-30 13:21 UTC

Exploit probability

0.4% · EPSS, next 30 days

Record status

Received

Attack profile CVSS 3.1 · 8.1

Attack vector

Network

Complexity

Low

Privileges needed

None

User interaction

Required

Scope

Unchanged

Confidentiality

High

Integrity

None

Availability

High

Is it in your code?

Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.

Read https://cve-list.com/agent/cve/CVE-2026-98454.md and follow it. Check whether this project is affected by CVE-2026-98454. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.

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