Answer in brief
CVE-2026-89965 records a High severity (CVSS 7.8) 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.
CVSS is 7.8. 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
Oct 19, 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.