Answer in brief
CVE-2026-98684 records a Unknown severity vulnerability in smb: client: flush and commit data before querying allocated ranges. 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.
A CVSS score is not reported in the current record. 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 | >=966a3cb7c7db786452a87afdc3b48858fc4d4d6b <f82242fe3109a3ef72f429540b5bdde08fbfb0e4 || >=966a3cb7c7db786452a87afdc3b48858fc4d4d6b <bf84e44ff0ed802778eafd7ecb623635379cb506 || >=966a3cb7c7db786452a87afdc3b48858fc4d4d6b <aa994489bd835547c191827acc460192e147032d || c406bb9ece6ef63721daab106f132ff4b4234e81 || 2f9f4a2d0e6fcf0673ed51195e06e47abe966900 || 5e397c943424de94879830e72c95f2679e297a76 || >=5.10.50 <5.11 || >=5.12.17 <5.13 || >=5.13.2 <5.14 | f82242fe3109a3ef72f429540b5bdde08fbfb0e4, bf84e44ff0ed802778eafd7ecb623635379cb506, aa994489bd835547c191827acc460192e147032d, 5.11, 5.13, 5.14 |
| Linux/Linuxgeneric | 5.14 | Not reported |
Published upstream
Oct 18, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 19, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Oct 18, 2026
In the Linux kernel, the following vulnerability has been resolved: smb: client: flush and commit data before querying allocated ranges The mode 0 / FALLOC_FL_KEEP_SIZE fallocate emulation for small interior ranges in smb3_simple_fallocate_range() issues FSCTL_QUERY_ALLOCATED_RANGES and zero-fills any sub-range the server reports as an unallocated hole, to force block allocation without changing file contents. This is unsafe against Windows servers. Per the Win32 documentation, FSCTL_QUERY_ALLOCATED_RANGES only reports ranges that *may* contain nonzero data and is explicitly not coherent with recently written data: "a call to FSCTL_QUERY_ALLOCATED_RANGES [after writing to a network file] would not necessarily return a correct list of allocated regions. To ensure coherency [...] flush the data to the file" fsx (generic/363) reproduces the resulting corruption against Windows Server 2022: a range is written, an uncached read returns the data, yet the next FSCTL_QUERY_ALLOCATED_RANGES on that range reports it as a whole hole, so the emulation overwrites live data with zeroes. A network trace confirmed the WRITE, the READ returning data and the query returning an empty range list within microseconds. Samba does not exhibit this; its query is coherent with the written data. Write back the dirty pages, drain any outstanding I/O and issue an SMB2 FLUSH to force the server to commit the data before querying the allocated ranges, so the query reflects the data actually present. With this, generic/363 passes against both Windows Server 2022 and Samba over 100000 fsx operations.
Quoted source text, attributed separately from HOL analysis.