VulnerabilityPublished 17 Sep 2026Updated 30 Oct 2026

CVE-2026-90170: Linux kernel · ksmbd: validate ipc response length before dereferencing its fields

Affects Linux kernelSource CVE Database V5

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Not known to be exploited · fixed in e9b33376bd07bca4175f7bcc2d6034ef250f8181 : patch Linux kernel soon.

Data as of 30 Oct 2026, 12:51 UTC

Severity

High

Rated High by Threat Radar's AI analysis · CVSS not yet scored by NVD

Thin evidence

One scorer or none

Patch: Available – fixed in e9b33376bd07bca4175f7bcc2d6034ef250f8181, c494fcf8e89e3c970e13d78ebe62bf5d8f2b1c52, 398cba4b646a6c08ff3d79e6b1e70e5ddae8a065 +7

Exploitation evidence

Disclosed: evidence found.
CVE published 17 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponized: A Metasploit exploit module or Exploit-DB entry exists (Metasploit scanner modules do not count), or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Upgrade to a fixed release listed under Affected software.

Affected software

Product	Affected	Fixed in
LinuxLinux	Affected >=6.6.141 <6.6.157 >=6.12.84 <6.12.110 >=6.18.25 <6.18.52 >=6.1.191 <6.2 >=7.0.2 <7.1	Fixed in e9b33376bd07bca4175f7bcc2d6034ef250f8181 c494fcf8e89e3c970e13d78ebe62bf5d8f2b1c52 398cba4b646a6c08ff3d79e6b1e70e5ddae8a065 17b7d1a2b4d5473df5dca8c9a07d65021806c23a 7.1 6.18.52 6.12.110 6.6.157 6.2 0aa8f94bfd4d818284c8a7ce0040d40ca1ec3595
LinuxLinux	Affected =7.1	Fixed in–

AI-suggested

This vulnerability has been fixed in Linux kernel versions 6.6.157, 6.12.110, 6.18.52, 6.2, and 7.1. Users and administrators should upgrade to these or later kernel versions to remediate the issue. No additional mitigation steps are indicated by the vendor advisory.

Description

A vulnerability in the Linux kernel's ksmbd component allowed improper validation of IPC response message length before dereferencing fields. This flaw could lead to out-of-bounds reads when processing short responses from the userspace ksmbd daemon. The issue was fixed in multiple Linux kernel versions including 6.6.157, 6.12.110, 6.18.52, 6.2, and 7.1.

Impact

The vulnerability can cause out-of-bounds memory reads in kernel space, which may lead to kernel crashes or potential information disclosure. There is no indication of known exploitation in the wild. The impact is limited to the ksmbd kernel module handling IPC responses.

Summary

The vulnerability in the Linux kernel's ksmbd subsystem arises because ipc_validate_msg() reads length fields from a response buffer before verifying that the buffer is large enough to contain the expected structure. Specifically, handle_response() sizes the response buffer based only on netlink attribute length and does not sufficiently guard against short responses. This can cause ipc_msg_send_request() to read beyond the allocated memory, resulting in a slab-out-of-bounds read detected by KASAN. The flaw was addressed by adding proper validation of the IPC response length before dereferencing its fields.

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 30 Oct 2026, 12:51 UTC

Technical details

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