Answer in brief
CVE-2026-89965 records a Unknown severity vulnerability in nvdimm/btt: reject an arena whose nfree is below the lane count. 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 | >=5212e11fde4d40fa627668b4f2222d20db488f71 <eb491343d2d1784121ad9af91c25b338c28913c3 || >=5212e11fde4d40fa627668b4f2222d20db488f71 <59d5cd1f42b4bab3609512c3cb3d3540d3d21da7 || >=5212e11fde4d40fa627668b4f2222d20db488f71 <f6c5313aae794ecca8f762c1a3493de5c266f120 || >=5212e11fde4d40fa627668b4f2222d20db488f71 <f9bf05c63b77d000e9c01f3e47af36973887d350 || >=5212e11fde4d40fa627668b4f2222d20db488f71 <6f79d1a5f2611a3d36e9312be5425cd9cb397c51 || >=5212e11fde4d40fa627668b4f2222d20db488f71 <6b1faf1f099f7060b5f1f2f0d024132581f1726e || >=5212e11fde4d40fa627668b4f2222d20db488f71 <9dfa11cef4750b67591307f2c62e47a23d60e4b7 || >=5212e11fde4d40fa627668b4f2222d20db488f71 <6a1f2e5ed9267ca19187038ac635393c165213ac | eb491343d2d1784121ad9af91c25b338c28913c3, 59d5cd1f42b4bab3609512c3cb3d3540d3d21da7, f6c5313aae794ecca8f762c1a3493de5c266f120, f9bf05c63b77d000e9c01f3e47af36973887d350, 6f79d1a5f2611a3d36e9312be5425cd9cb397c51, 6b1faf1f099f7060b5f1f2f0d024132581f1726e, 9dfa11cef4750b67591307f2c62e47a23d60e4b7, 6a1f2e5ed9267ca19187038ac635393c165213ac |
| Linux/Linuxgeneric | 4.2 | Not reported |
Published upstream
Sep 16, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Sep 16, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Sep 16, 2026
In the Linux kernel, the following vulnerability has been resolved: nvdimm/btt: reject an arena whose nfree is below the lane count The BTT info block's nfree field, the number of reserve free blocks, is read from the medium without validation. btt_freelist_init() and btt_rtt_init() size the per-lane freelist[] and rtt[] arrays by nfree, but the I/O path indexes them by the lane from nd_region_acquire_lane(), which is bounded by nd_region->num_lanes (ND_MAX_LANES), not by nfree. A crafted or foreign arena whose nfree is below the lane count makes freelist[lane]/rtt[lane] run past the allocation: an out-of-bounds write. btt.rst documents the nlanes = min(nfree, num_cpus) invariant, which the code does not currently honor: num_lanes is ND_MAX_LANES regardless of nfree. Reject an arena whose nfree is below num_lanes at discovery, before the per-lane arrays are allocated, enforcing that invariant.
Quoted source text, attributed separately from HOL analysis.