CVE-2026-89781 — In the Linux kernel, the following vulnerability has been resolved: fs/ntfs3: fix…
In the Linux kernel, the following vulnerability has been resolved: fs/ntfs3: fix out-of-bounds read in read_log_rec_buf() read_log_rec_buf() copies a log record into a caller buffer starting at u32 off = lsn_to_page_off(log, lsn) + log->record_header_len; log->record_header_len (and log->data_off, used for the following pages) comes verbatim from the on-disk restart area and is only checked for 8-byte alignment in is_rst_area_valid(), so off can exceed log->page_size. "tail = log->page_size - off" then underflows and memcpy() reads past the page_size-sized buffer returned by read_log_page(), spilling adjacent slab memory into the replay buffer. This is reachable by mounting a crafted NTFS image: BUG: KASAN: slab-out-of-bounds in read_log_rec_buf+0x216/0x580 Read of size 64 at addr ffff88800a877ff8 by task exploit/127 read_log_rec_buf fs/ntfs3/fslog.c:2299 log_replay fs/ntfs3/fslog.c:4216 ntfs_loadlog_and_replay fs/ntfs3/fsntfs.c:324 ntfs_fill_super fs/ntfs3/super.c:1392 get_tree_bdev_flags fs/super.c:1694 __x64_sys_mount fs/namespace.c:4360 The buggy address is located 4088 bytes to the right of the 4096-byte region [ffff88800a876000, ffff88800a877000) Reject an in-page offset outside the current page before the copy. [almaz.alexandrovich@paragon-software.com: replaced the >= sign with >]
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- Technical severity (high)+6
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Affected products have not been identified by the sources yet: follow the vendor advisory and map candidate assets by component name.
- No fix documented in the sources: reduce exposure and monitor the vendor advisory.
- Search available logs for exploit probes, errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
Affected products not yet identified by the sources.
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 8.4 | CVSS 3.1 | High | 2.5 | 5.9 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 via NIST National Vulnerability Database |
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H (score shown at the top: 416baaa9-dc9f-4396-8d5f-8c081fb06d67) Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Local/physical vector: focus on endpoint telemetry (EDR) from affected hosts.
Timeline
What happened to this CVE, newest first.
- 2026
- Record published
- CVSS changed · 8.4
- Source status changed · → Received
- Record created in this database
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× Official description updated · Oct 15, 2026 – Oct 15, 2026
References
7 on the record
- git.kernel.org/stable/c/1b2d31f1083beb80c55d1152249f652c1445a559
- git.kernel.org/stable/c/700973cc65db405bde0368ccf88699390150943e
- git.kernel.org/stable/c/df099bfdb57773ba7f40f8a9dcc82e75af277922
- git.kernel.org/stable/c/53e56f7aa1d0f950a8bc2e4cdb3ba9fe45967531
- git.kernel.org/stable/c/49f7cbc902b08b56eb7d2633163ecc57a0e7145a
- git.kernel.org/stable/c/de603b9d377fab57a5e6432fa84a9f36b32c1636
- git.kernel.org/stable/c/74a83aa05f73033af719771ab1f0c269928b4865
Elsewhere on this site
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No FIRST EPSS score.
- No affected product/version with evidence in the sources.
- No fixed version, patch or mitigation documented.
- No CISA SSVC assessment.
- No CWE classification.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2026-89781 is "In the Linux kernel, the following vulnerability has been resolved: fs/ntfs3: fix…", rated High. Affected products have not been identified by the sources yet. It is not in CISA KEV, which does not rule out exploitation. CVSS 8.4 describes technical severity. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
Comments
Moderated technical discussion. Read the community guidelines.
No comments yet.
Sign in or create an account to comment and suggest corrections.