# CVE-2026-89615

## Summary

- **CVE ID:** CVE-2026-89615
- **Severity:** HIGH
- **CVSS Score:** 8.4 (CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H)
- **CWE:** N/A
- **Published:** Sep 11, 2026
- **Last Modified:** Sep 14, 2026

## Description

In the Linux kernel, the following vulnerability has been resolved:

fs/ntfs3: bound page_lcns[] index by the log record

The copy_lcns loop and the redo shorten loop index page_lcns[] at j + i,
where i runs up to the log record's lcns_follow. That count is checked only
against the record's own length, not the target entry, so check_dp_table()
(which validates the entry's lcns_follow) does not cover it: the copy_lcns
entry may even be freshly allocated after that check, and find_dp() bounds j
but not i. A crafted record thus overflows page_lcns[] of an otherwise valid
entry.

Add dp_range_ok() and reject, before each loop, any record whose run does
not fit the entry. These are the only two page_lcns[] accesses indexed by
the record rather than the entry, so together with the entry validation
every access is now bounded.

[almaz.alexandrovich@paragon-software.com: original patch contained changes to the problem already handled, applied partly]

## Affected Products

- Linux — Linux (b46acd6a6a627d876898e1c84d3f84902264b445)
- Linux — Linux (5.15)
- Linux — Linux (0)
- Linux — Linux (6.12.109)
- Linux — Linux (6.18.50)
- Linux — Linux (7.2.4)
- Linux — Linux (7.3-rc1)
- Linux — Linux (5.15.221)
- Linux — Linux (6.1.188)
- Linux — Linux (6.6.157)

## References

- [CNA](https://git.kernel.org/stable/c/f4c1bc6d7331f344ffcea93c2a37badcbe15baa6)
- [CNA](https://git.kernel.org/stable/c/7ccb94901f38a062034b56b43c774050b113758f)
- [CNA](https://git.kernel.org/stable/c/1135ebc225996b3ac1a295652b19a0a706737a6c)
- [CNA](https://git.kernel.org/stable/c/6f7b9dbdc1b7520206abce0049bdd143eb536e75)
- [CNA](https://git.kernel.org/stable/c/31fdd11f75da9823500168cecb07aa45130915a3)
- [CNA](https://git.kernel.org/stable/c/bb742d1030864c0fe140666f639428ba4e90b2ca)
- [CNA](https://git.kernel.org/stable/c/61ca8cbbf68f77f25b699ed4358bd232f94ed43b)

## Exploitation Prediction (EPSS)

- **EPSS Score:** 0.15%
- **EPSS Percentile:** 4.9

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_Exported from OnDuty AI Vulnerability Intelligence on 2026-09-18._