CVE-2026-64531Public exploit

Local privilege escalation via nested attribute truncation

Published Jul 27, 2026 · Updated Jul 27, 2026

Length inconsistency in affected Linux Kernel releases allows local users to gain root via oversized Open vSwitch nested actions. Open vSwitch closes generated CLONE or CT containers larger than U16_MAX with a truncated u16 nla_len, so later dump or teardown parsing treats trailing bytes as independent actions. Exploitation requires the Open vSwitch kernel module and local control of a network namespace, and successful abuse can alter kernel memory and elevate privileges to root.

CVSS severity7.8
High
EPSS probability0.38%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Length inconsistency in affected Linux Kernel releases allows local users to gain root via oversized Open vSwitch nested actions. Open vSwitch closes generated CLONE or CT containers larger than U16_MAX with a truncated u16 nla_len, so later dump or teardown parsing treats trailing bytes as independent actions. Exploitation requires the Open vSwitch kernel module and local control of a network namespace, and successful abuse can alter kernel memory and elevate privileges to root.

The record

CVE
CVE-2026-64531
Published
Jul 27, 2026
Updated
Jul 27, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
CWE-130, T1068
Attack vector
local
Privileges
authenticated

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

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=057dbc5b72e9fcac439cd561c3a539b8a0edeb92 <ab855641241387db062a5e41d9ad6b8561542572
  2. Affected versionversion=2532adbfe917c0e71dba2650ffc6efe396314c87 <c66bd2626c2764f23764ff0f8277f44a9cfe8349
  3. Affected versionversion=4b1a0ee6164c7204c68ab5a9c48c07bfe8852485 <d573250d228401f707f4dbc09d11227a6215ee5f
  4. Affected versionversion=5.15.180 <5.15.212
  5. Affected versionversion=6.1.132 <6.1.178
  6. Affected versionversion=6.12.20 <6.12.97
  7. Affected versionversion=6.13.8 <6.14
  8. Affected versionversion=6.14
  9. Affected versionversion=6.6.84 <6.6.145
  10. Affected versionversion=6b099d285d7ed324494b6d684f377aa103856118
  11. Affected versionversion=a1e64addf3ff9257b45b78bc7d743781c3f41340 <1b41cbe05b184f8861712f0806cc0c4f5d8c6dfe
  12. Affected versionversion=a1e64addf3ff9257b45b78bc7d743781c3f41340 <3f1f755366687d051174739fb99f7d560202f60b
  13. Affected versionversion=a1e64addf3ff9257b45b78bc7d743781c3f41340 <dbd14f736be02cfe73049bd801af89becd1a0749
  14. Affected versionversion=e6610f9c08b4c04cf7949c10fc246c071d00e935 <f1efff8858403191361a01269c6fe8dd7f55a385

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=057dbc5b72e9fcac439cd561c3a539b8a0edeb92 <ab855641241387db062a5e41d9ad6b8561542572; version=2532adbfe917c0e71dba2650ffc6efe396314c87 <c66bd2626c2764f23764ff0f8277f44a9cfe8349; version=4b1a0ee6164c7204c68ab5a9c48c07bfe8852485 <d573250d228401f707f4dbc09d11227a6215ee5f; version=5.15.180 <5.15.212; version=6.1.132 <6.1.178; version=6.12.20 <6.12.97; version=6.13.8 <6.14; version=6.14; version=6.6.84 <6.6.145; version=6b099d285d7ed324494b6d684f377aa103856118; version=a1e64addf3ff9257b45b78bc7d743781c3f41340 <1b41cbe05b184f8861712f0806cc0c4f5d8c6dfe; version=a1e64addf3ff9257b45b78bc7d743781c3f41340 <3f1f755366687d051174739fb99f7d560202f60b; version=a1e64addf3ff9257b45b78bc7d743781c3f41340 <dbd14f736be02cfe73049bd801af89becd1a0749; version=e6610f9c08b4c04cf7949c10fc246c071d00e935 <f1efff8858403191361a01269c6fe8dd7f55a385

Published CVSS scores

7.8kernel.orgCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
7.8Red HatCVSS: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 exploitPublished

Weakness, pattern, technique

CWE-130Improper Handling of Length Parameter Inconsistency
T1068Exploitation for Privilege Escalation

Public exploit references

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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