CVE-2026-90161

Kernel-memory disclosure via malformed EROFS pclusters

Published Sep 17, 2026 · Updated Sep 18, 2026

Out-of-bounds read in Linux EROFS allows attackers to expose kernel memory through a crafted filesystem image. z_erofs_map_blocks_fo treats an invalid metadata-tail pcluster as interlaced, and z_erofs_transform_plain then copies past a mapped page into the output folio. Exploitation requires a victim or automounter to mount the image and read its compressed tail; the read exposes adjacent kernel memory and can crash the kernel.

CVSS severity7.1
High
EPSS probability0.18%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Out-of-bounds read in Linux EROFS allows attackers to expose kernel memory through a crafted filesystem image. z_erofs_map_blocks_fo treats an invalid metadata-tail pcluster as interlaced, and z_erofs_transform_plain then copies past a mapped page into the output folio. Exploitation requires a victim or automounter to mount the image and read its compressed tail; the read exposes adjacent kernel memory and can crash the kernel.

The record

CVE
CVE-2026-90161
Published
Sep 17, 2026
Updated
Sep 18, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
T1204.002
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 17, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 18, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=6.0.16 <6.1
  2. Affected versionversion=6.1
  3. Affected versionversion=7d6ef8277e44c22f894d54d26ddb36c22d60712d
  4. Affected versionversion=fdffc091e6f94602558bba712b51bc16f79fd6d5 <451027c642e752420e1a04237db9ce7b35cee595
  5. Affected versionversion=fdffc091e6f94602558bba712b51bc16f79fd6d5 <862427ebb81d1f6abbf74d799790e1694b37b187
  6. Affected versionversion=fdffc091e6f94602558bba712b51bc16f79fd6d5 <ddb7ea4fd99bf6c4314d1dfca18aec6945ce8054

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=6.0.16 <6.1; version=6.1; version=7d6ef8277e44c22f894d54d26ddb36c22d60712d; version=fdffc091e6f94602558bba712b51bc16f79fd6d5 <451027c642e752420e1a04237db9ce7b35cee595; version=fdffc091e6f94602558bba712b51bc16f79fd6d5 <862427ebb81d1f6abbf74d799790e1694b37b187; version=fdffc091e6f94602558bba712b51bc16f79fd6d5 <ddb7ea4fd99bf6c4314d1dfca18aec6945ce8054

Published CVSS scores

7.1Linux CNACVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Activity data is delayed. The latest report is Sep 28, 2026.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1204.002Malicious File

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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