CVE-2026-99273
ksmbd: reserve space for the UTF-16 terminator in stream info
Description
In the Linux kernel, the following vulnerability has been resolved: ksmbd: reserve space for the UTF-16 terminator in stream info smb_strtoUTF16() always writes a terminating zero UTF-16 unit after the converted characters, but get_file_stream_info() budgets only sizeof(struct smb2_file_stream_info) + streamlen * 2 for a stream entry and sizeof(struct smb2_file_stream_info) + 7 * 2 for the trailing "::$DATA" entry. When an entry exactly fills the 448-byte small response buffer, the terminator is written two bytes past the allocation. Reserve one extra UTF-16 unit in both budget checks. The terminator is not part of the wire format, so the reported lengths are unchanged.
INFO
Published Date :
Nov. 7, 2026, 2:17 p.m.
Last Modified :
Nov. 7, 2026, 2:17 p.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Solution
- Apply the kernel patch for the ksmbd vulnerability.
- Ensure UTF-16 terminator space is reserved in budget checks.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-99273.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-99273 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-99273
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
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The following list is the news that have been mention
CVE-2026-99273 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-99273 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Nov. 07, 2026
Action Type Old Value New Value Added Description In the Linux kernel, the following vulnerability has been resolved: ksmbd: reserve space for the UTF-16 terminator in stream info smb_strtoUTF16() always writes a terminating zero UTF-16 unit after the converted characters, but get_file_stream_info() budgets only sizeof(struct smb2_file_stream_info) + streamlen * 2 for a stream entry and sizeof(struct smb2_file_stream_info) + 7 * 2 for the trailing "::$DATA" entry. When an entry exactly fills the 448-byte small response buffer, the terminator is written two bytes past the allocation. Reserve one extra UTF-16 unit in both budget checks. The terminator is not part of the wire format, so the reported lengths are unchanged. Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/99xxx/CVE-2026-99273.json">CVE-2026-99273</a> Added Reference https://git.kernel.org/stable/c/06a751809ebd33e95b05bf733697318a17a4872b Added Reference https://git.kernel.org/stable/c/0e64f89563164719ceb1aa33f2a8bfd6391fa340 Added Reference https://git.kernel.org/stable/c/a025c4991a7d83edc4dd339e3ea86d8ff6226eca