CVE-2026-43284Public exploit

Local root escalation via shared fragment decryption

Published May 8, 2026 · Updated May 8, 2026

Unsafe in-place decryption in Linux Kernel 4.11 and later allows local users to gain root privileges through shared skb fragments. IPv4 and IPv6 datagram splice paths fail to mark pipe-backed UDP skb fragments as shared, so ESP input decrypts them in place without copy-on-write protection. Exploitation requires low-privileged local access and permission to create a user or network namespace, and it enables page-cache writes to sensitive files.

CVSS severity7.8
High
EPSS probability93.23%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Unsafe in-place decryption in Linux Kernel 4.11 and later allows local users to gain root privileges through shared skb fragments. IPv4 and IPv6 datagram splice paths fail to mark pipe-backed UDP skb fragments as shared, so ESP input decrypts them in place without copy-on-write protection. Exploitation requires low-privileged local access and permission to create a user or network namespace, and it enables page-cache writes to sensitive files.

The record

CVE
CVE-2026-43284
Published
May 8, 2026
Updated
May 8, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
CWE-123, T1068
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. May 8, 2026CVE publishedPublication date reported by the CVE source.
  2. May 8, 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=4.11
  2. Affected versionversion=cac2661c53f35cbe651bef9b07026a5a05ab8ce0 <50ed1e7873100f77abad20fd31c51029bc49cd03
  3. Affected versionversion=cac2661c53f35cbe651bef9b07026a5a05ab8ce0 <52646cbd00e765a6db9c3afe9535f26218276034
  4. Affected versionversion=cac2661c53f35cbe651bef9b07026a5a05ab8ce0 <5d55c7336f8032d434adcc5fab987ccc93a44aec
  5. Affected versionversion=cac2661c53f35cbe651bef9b07026a5a05ab8ce0 <71a1d9d985d26716f74d21f18ee8cac821b06e97
  6. Affected versionversion=cac2661c53f35cbe651bef9b07026a5a05ab8ce0 <8253aab4659ca16116b522203c2a6b18dccacea7
  7. Affected versionversion=cac2661c53f35cbe651bef9b07026a5a05ab8ce0 <a6cb440f274a22456ef3e86b457344f1678f38f9
  8. Affected versionversion=cac2661c53f35cbe651bef9b07026a5a05ab8ce0 <ab8b995323e5237041472d07e5055f5f7dcdf15b
  9. Affected versionversion=cac2661c53f35cbe651bef9b07026a5a05ab8ce0 <b54edf1e9a3fd3491bdcb82a21f8d21315271e0d
  10. Affected versionversion=cac2661c53f35cbe651bef9b07026a5a05ab8ce0 <fe785bb3a8096dffcc4048a85cd0c83337eeecad

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=4.11; version=cac2661c53f35cbe651bef9b07026a5a05ab8ce0 <50ed1e7873100f77abad20fd31c51029bc49cd03; version=cac2661c53f35cbe651bef9b07026a5a05ab8ce0 <52646cbd00e765a6db9c3afe9535f26218276034; version=cac2661c53f35cbe651bef9b07026a5a05ab8ce0 <5d55c7336f8032d434adcc5fab987ccc93a44aec; version=cac2661c53f35cbe651bef9b07026a5a05ab8ce0 <71a1d9d985d26716f74d21f18ee8cac821b06e97; version=cac2661c53f35cbe651bef9b07026a5a05ab8ce0 <8253aab4659ca16116b522203c2a6b18dccacea7; version=cac2661c53f35cbe651bef9b07026a5a05ab8ce0 <a6cb440f274a22456ef3e86b457344f1678f38f9; version=cac2661c53f35cbe651bef9b07026a5a05ab8ce0 <ab8b995323e5237041472d07e5055f5f7dcdf15b; version=cac2661c53f35cbe651bef9b07026a5a05ab8ce0 <b54edf1e9a3fd3491bdcb82a21f8d21315271e0d; version=cac2661c53f35cbe651bef9b07026a5a05ab8ce0 <fe785bb3a8096dffcc4048a85cd0c83337eeecad

Published CVSS scores

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.

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

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-123Write-what-where Condition
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

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo