Answer in brief
CVE-2026-46139 records a Medium severity (CVSS 5.5) vulnerability in smb: client: use kzalloc to zero-initialize security descriptor buffer. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). 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 5.5. 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). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=1593ddb37bd124c131fe635397df68e854a03108 <4c3ed344a970aad51388ac3b0145b98318f0e21f || >=da087905e3270e2291c0afae39a28e7d183e5ec3 <941a1e6eb35440336913afc88a82103291956d5d || >=62e7dd0a39c2d0d7ff03274c36df971f1b3d2d0d <be1ef9512a3f5a755895c24f31b334342f4aa15b || >=62e7dd0a39c2d0d7ff03274c36df971f1b3d2d0d <9bdb2ca31368b7671949dfb94a5d57ffccd01edd || >=62e7dd0a39c2d0d7ff03274c36df971f1b3d2d0d <5e489c6c47a2ac15edbaca153b9348e42c1eacab || 191f2f444745087c3c51fd6042a0e25f42315ab0 || >=6.12.23 <6.12.88 || >=6.13.11 <6.14 | 4c3ed344a970aad51388ac3b0145b98318f0e21f, 941a1e6eb35440336913afc88a82103291956d5d, be1ef9512a3f5a755895c24f31b334342f4aa15b, 9bdb2ca31368b7671949dfb94a5d57ffccd01edd, 5e489c6c47a2ac15edbaca153b9348e42c1eacab, 6.12.88, 6.14 |
| Linux/Linuxgeneric | 6.14 | Not reported |
Published upstream
May 28, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Jun 24, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Jun 24, 2026
In the Linux kernel, the following vulnerability has been resolved: smb: client: use kzalloc to zero-initialize security descriptor buffer Commit 62e7dd0a39c2d ("smb: common: change the data type of num_aces to le16") split struct smb_acl's __le32 num_aces field into __le16 num_aces and __le16 reserved. The reserved field corresponds to Sbz2 in the MS-DTYP ACL wire format, which must be zero [1]. When building an ACL descriptor in build_sec_desc(), we are using a kmalloc()'ed descriptor buffer and writing the fields explicitly using le16() writes now. This never writes to the 2 byte reserved field, leaving it as uninitialized heap data. When the reserved field happens to contain non-zero slab garbage, Samba rejects the security descriptor with "ndr_pull_security_descriptor failed: Range Error", causing chmod to fail with EINVAL. Change kmalloc() to kzalloc() to ensure the entire buffer is zero-initialized. [1] https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-dtyp/20233ed8-a6c6-4097-aafa-dd545ed24428
Quoted source text, attributed separately from HOL analysis.