Answer in brief
CVE-2026-64400 records a High severity (CVSS 8.6) vulnerability in ksmbd: prevent path traversal bypass by restricting caseless retry. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic), Linux/Linux (generic), Linux/Linux (generic) and additional mapped packages. Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 8.6. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic), Linux/Linux (generic), Linux/Linux (generic) and additional mapped packages. Check affected ranges and fixed versions before updating.
| Product | Affected versions | Fixed versions |
|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | Not reported | Not reported |
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=74d7970febf7e9005375aeda0df821d2edffc9f7 <8c9a4f1327eb71efbf14842e7b8a6d965077eb67 || >=74d7970febf7e9005375aeda0df821d2edffc9f7 <54bab9ba5a9f156ffa9324fcbe5a356fd0242f95 || 019aae488dbc67c97a33db03652e20e2c9e3afa7 || 6927ffe7479c72e7ebf885507227266a75f7c97d || ef6cc1c465786b3e4e735d1ab8b616b3e94402df || >=5.15.145 <5.16 || >=6.1.71 <6.2 || >=6.3.10 <6.4 | 8c9a4f1327eb71efbf14842e7b8a6d965077eb67, 54bab9ba5a9f156ffa9324fcbe5a356fd0242f95, 5.16, 6.2, 6.4 |
| Linux/Linuxgeneric | 6.4 | Not reported |
| Linux/Linuxgeneric | >=74d7970febf7e9005375aeda0df821d2edffc9f7 <cfb5a56c218888f9d74165dff0c282cd0be97983 || >=74d7970febf7e9005375aeda0df821d2edffc9f7 <8c9a4f1327eb71efbf14842e7b8a6d965077eb67 || >=74d7970febf7e9005375aeda0df821d2edffc9f7 <54bab9ba5a9f156ffa9324fcbe5a356fd0242f95 || 019aae488dbc67c97a33db03652e20e2c9e3afa7 || 6927ffe7479c72e7ebf885507227266a75f7c97d || ef6cc1c465786b3e4e735d1ab8b616b3e94402df || >=5.15.145 <5.16 || >=6.1.71 <6.2 || >=6.3.10 <6.4 | cfb5a56c218888f9d74165dff0c282cd0be97983, 8c9a4f1327eb71efbf14842e7b8a6d965077eb67, 54bab9ba5a9f156ffa9324fcbe5a356fd0242f95, 5.16, 6.2, 6.4 |
| Linux/Linuxgeneric | >=74d7970febf7e9005375aeda0df821d2edffc9f7 <eec1dd2586c4016b7555a5d047db2b3756459fb2 || >=74d7970febf7e9005375aeda0df821d2edffc9f7 <a1c331d98313380c38f616c8b28b890ec8ef9c28 || >=74d7970febf7e9005375aeda0df821d2edffc9f7 <cfb5a56c218888f9d74165dff0c282cd0be97983 || >=74d7970febf7e9005375aeda0df821d2edffc9f7 <8c9a4f1327eb71efbf14842e7b8a6d965077eb67 || >=74d7970febf7e9005375aeda0df821d2edffc9f7 <54bab9ba5a9f156ffa9324fcbe5a356fd0242f95 || 019aae488dbc67c97a33db03652e20e2c9e3afa7 || 6927ffe7479c72e7ebf885507227266a75f7c97d || ef6cc1c465786b3e4e735d1ab8b616b3e94402df || >=5.15.145 <5.16 || >=6.1.71 <6.2 || >=6.3.10 <6.4 | eec1dd2586c4016b7555a5d047db2b3756459fb2, a1c331d98313380c38f616c8b28b890ec8ef9c28, cfb5a56c218888f9d74165dff0c282cd0be97983, 8c9a4f1327eb71efbf14842e7b8a6d965077eb67, 54bab9ba5a9f156ffa9324fcbe5a356fd0242f95, 5.16, 6.2, 6.4 |
| Linux/Linuxgeneric | >=6927ffe7479c72e7ebf885507227266a75f7c97d <21f050439db157f2afcc19885dec14549ca6ffc0 || >=74d7970febf7e9005375aeda0df821d2edffc9f7 <eec1dd2586c4016b7555a5d047db2b3756459fb2 || >=74d7970febf7e9005375aeda0df821d2edffc9f7 <a1c331d98313380c38f616c8b28b890ec8ef9c28 || >=74d7970febf7e9005375aeda0df821d2edffc9f7 <cfb5a56c218888f9d74165dff0c282cd0be97983 || >=74d7970febf7e9005375aeda0df821d2edffc9f7 <8c9a4f1327eb71efbf14842e7b8a6d965077eb67 || >=74d7970febf7e9005375aeda0df821d2edffc9f7 <54bab9ba5a9f156ffa9324fcbe5a356fd0242f95 || 019aae488dbc67c97a33db03652e20e2c9e3afa7 || ef6cc1c465786b3e4e735d1ab8b616b3e94402df || >=6.1.71 <6.1.191 || >=5.15.145 <5.16 || >=6.3.10 <6.4 | 21f050439db157f2afcc19885dec14549ca6ffc0, eec1dd2586c4016b7555a5d047db2b3756459fb2, a1c331d98313380c38f616c8b28b890ec8ef9c28, cfb5a56c218888f9d74165dff0c282cd0be97983, 8c9a4f1327eb71efbf14842e7b8a6d965077eb67, 54bab9ba5a9f156ffa9324fcbe5a356fd0242f95, 6.1.191, 5.16, 6.4 |
Published upstream
Jul 25, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 30, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 5, 2026
In the Linux kernel, the following vulnerability has been resolved: ksmbd: prevent path traversal bypass by restricting caseless retry ksmbd_vfs_path_lookup() enforces LOOKUP_BENEATH to restrict path resolution within the share root. When a crafted path attempts to escape the share boundary using parent-directory components ('..'), vfs_path_parent_lookup() detects this and immediately fails, returning -EXDEV. However, a bug exists in __ksmbd_vfs_kern_path() under caseless mode. The function fails to intercept the -EXDEV error and erroneously falls through to the caseless retry logic, which is intended only for genuinely missing files. During this retry process, the path is reconstructed, leading to an unintended LOOKUP_BENEATH bypass that allows write-capable users to create zero-length files or directories outside the exported share. Fix this by ensuring that the execution only proceeds to the caseless lookup retry when the error is specifically -ENOENT. Any other errors, such as -EXDEV from a path traversal attempt, must be returned immediately.
Quoted source text, attributed separately from HOL analysis.