CVE-2026-64548

Local kernel compromise via BPF length overflow

Published Jul 27, 2026 · Updated Jul 27, 2026

Out-of-bounds write in the Linux Kernel allows local users to corrupt kernel memory through a crafted BPF message length. In bpf_msg_push_data(), the copy fallback adds two unbounded u32 values for an allocation size, allowing wraparound before an out-of-bounds memcpy. The path requires a local sendmsg() or sendto() call on a sockmap- or kTLS-attached socket and can expose or overwrite kernel memory, escalate privileges, or crash the host.

CVSS severity8.4
High
EPSS probability0.14%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Out-of-bounds write in the Linux Kernel allows local users to corrupt kernel memory through a crafted BPF message length. In bpf_msg_push_data(), the copy fallback adds two unbounded u32 values for an allocation size, allowing wraparound before an out-of-bounds memcpy. The path requires a local sendmsg() or sendto() call on a sockmap- or kTLS-attached socket and can expose or overwrite kernel memory, escalate privileges, or crash the host.

The record

CVE
CVE-2026-64548
Published
Jul 27, 2026
Updated
Jul 27, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
T1068
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 27, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 27, 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=4.20
  2. Affected versionversion=6fff607e2f14bd7c63c06c464a6f93b8efbabe28 <0c0a8ed85349dae298712d79cb276acfeb794d82
  3. Affected versionversion=6fff607e2f14bd7c63c06c464a6f93b8efbabe28 <4e40056bb5c829f0423f0a6694a0477726d2147e
  4. Affected versionversion=6fff607e2f14bd7c63c06c464a6f93b8efbabe28 <888706a76286c547bd035432602571e8024b5305
  5. Affected versionversion=6fff607e2f14bd7c63c06c464a6f93b8efbabe28 <a12b1575f9feabd91695a9e9d004862f7195fa25
  6. Affected versionversion=6fff607e2f14bd7c63c06c464a6f93b8efbabe28 <bd004716ba75fed6d185795c85cdc92540ebeaab
  7. Affected versionversion=6fff607e2f14bd7c63c06c464a6f93b8efbabe28 <db77b6bb6e6edb79b10b4efcce346eec5582d588
  8. Affected versionversion=6fff607e2f14bd7c63c06c464a6f93b8efbabe28 <f1644c9508d24f50dd9e8ebe8d3ba86e0996d2f5
  9. Affected versionversion=6fff607e2f14bd7c63c06c464a6f93b8efbabe28 <ff39d0e3b4feeb65ca43c453d7c75fdf872ded0d

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=4.20; version=6fff607e2f14bd7c63c06c464a6f93b8efbabe28 <0c0a8ed85349dae298712d79cb276acfeb794d82; version=6fff607e2f14bd7c63c06c464a6f93b8efbabe28 <4e40056bb5c829f0423f0a6694a0477726d2147e; version=6fff607e2f14bd7c63c06c464a6f93b8efbabe28 <888706a76286c547bd035432602571e8024b5305; version=6fff607e2f14bd7c63c06c464a6f93b8efbabe28 <a12b1575f9feabd91695a9e9d004862f7195fa25; version=6fff607e2f14bd7c63c06c464a6f93b8efbabe28 <bd004716ba75fed6d185795c85cdc92540ebeaab; version=6fff607e2f14bd7c63c06c464a6f93b8efbabe28 <db77b6bb6e6edb79b10b4efcce346eec5582d588; version=6fff607e2f14bd7c63c06c464a6f93b8efbabe28 <f1644c9508d24f50dd9e8ebe8d3ba86e0996d2f5; version=6fff607e2f14bd7c63c06c464a6f93b8efbabe28 <ff39d0e3b4feeb65ca43c453d7c75fdf872ded0d

Published CVSS scores

8.4kernel.orgCVSS:3.1/AV:L/AC:L/PR:N/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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1068Exploitation for Privilege Escalation

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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