CVE-2026-64053

Kernel memory disclosure via overwritten integrity vector count

Published Jul 19, 2026 · Updated Jul 19, 2026

An out-of-bounds read in the Linux Kernel block-integrity path allows local users to expose kernel memory through crafted integrity I/O. bio_integrity_copy_user() replaces the bounce segment's bip_vcnt with nr_vecs although bip_max_vcnt is one, so write-side gap-merge checks read beyond bip_vec[]. Reachability requires access to an integrity-capable block device; the resulting invalid read can disclose adjacent kernel heap data or crash the host.

CVSS severity7.8
High
EPSS probability0.13%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

An out-of-bounds read in the Linux Kernel block-integrity path allows local users to expose kernel memory through crafted integrity I/O. bio_integrity_copy_user() replaces the bounce segment's bip_vcnt with nr_vecs although bip_max_vcnt is one, so write-side gap-merge checks read beyond bip_vec[]. Reachability requires access to an integrity-capable block device; the resulting invalid read can disclose adjacent kernel heap data or crash the host.

The record

CVE
CVE-2026-64053
Published
Jul 19, 2026
Updated
Jul 19, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
Unavailable
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Jul 19, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 19, 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=3991657ae7074c3c497bf095093178bed37ea1b4 <066be1439593a381b1a29663becfcfe0c92363e7
  2. Affected versionversion=3991657ae7074c3c497bf095093178bed37ea1b4 <0d48654af4d1390c888389206cc13b51b82c30e6
  3. Affected versionversion=3991657ae7074c3c497bf095093178bed37ea1b4 <637ad3a56a3b889527d1dacea6fea2a8bd648140
  4. Affected versionversion=3991657ae7074c3c497bf095093178bed37ea1b4 <d18160c9525c63c203656fefd847e94b538cd4a4
  5. Affected versionversion=6.11

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=3991657ae7074c3c497bf095093178bed37ea1b4 <066be1439593a381b1a29663becfcfe0c92363e7; version=3991657ae7074c3c497bf095093178bed37ea1b4 <0d48654af4d1390c888389206cc13b51b82c30e6; version=3991657ae7074c3c497bf095093178bed37ea1b4 <637ad3a56a3b889527d1dacea6fea2a8bd648140; version=3991657ae7074c3c497bf095093178bed37ea1b4 <d18160c9525c63c203656fefd847e94b538cd4a4; version=6.11

Published CVSS scores

7.8LinuxCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/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.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

No sourced classifications are available.

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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