CVE-2026-68284

System crash via stale cork double-free

Published Aug 10, 2026 · Updated Aug 10, 2026

Use-after-free in the Linux kernel's BPF sockmap code allows local users to crash the system through concurrent sends on one socket. tcp_bpf_sendmsg() retains msg_tx while sk_stream_wait_memory() drops the socket lock, then compares it with a changed psock->cork and frees the already released shared cork again. An ordinary local process can trigger the flaw after a privileged component installs the sockmap program; otherwise creating that setup requires CAP_SYS_ADMIN or root.

CVSS severity7.8
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

Use-after-free in the Linux kernel's BPF sockmap code allows local users to crash the system through concurrent sends on one socket. tcp_bpf_sendmsg() retains msg_tx while sk_stream_wait_memory() drops the socket lock, then compares it with a changed psock->cork and frees the already released shared cork again. An ordinary local process can trigger the flaw after a privileged component installs the sockmap program; otherwise creating that setup requires CAP_SYS_ADMIN or root.

The record

CVE
CVE-2026-68284
Published
Aug 10, 2026
Updated
Aug 10, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
CWE-825, T1068
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 10, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 10, 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=604326b41a6fb9b4a78b6179335decee0365cd8c <2d66a033864e27ab8d5e44cb36f31d9d2413bee4
  3. Affected versionversion=604326b41a6fb9b4a78b6179335decee0365cd8c <752b1159ed5d0c48fe169a3721b96660a9822aa1
  4. Affected versionversion=604326b41a6fb9b4a78b6179335decee0365cd8c <786d690257ec7a0c839f8710456e444ce3f1348b
  5. Affected versionversion=604326b41a6fb9b4a78b6179335decee0365cd8c <cde4d6bcd9b73073c66498f6723c7b364c4dbc18
  6. Affected versionversion=604326b41a6fb9b4a78b6179335decee0365cd8c <ee762f684eefa59de34d9ed93cab08336e834f47

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=4.20; version=604326b41a6fb9b4a78b6179335decee0365cd8c <2d66a033864e27ab8d5e44cb36f31d9d2413bee4; version=604326b41a6fb9b4a78b6179335decee0365cd8c <752b1159ed5d0c48fe169a3721b96660a9822aa1; version=604326b41a6fb9b4a78b6179335decee0365cd8c <786d690257ec7a0c839f8710456e444ce3f1348b; version=604326b41a6fb9b4a78b6179335decee0365cd8c <cde4d6bcd9b73073c66498f6723c7b364c4dbc18; version=604326b41a6fb9b4a78b6179335decee0365cd8c <ee762f684eefa59de34d9ed93cab08336e834f47

Published CVSS scores

7.8Linux Kernel CVE TeamCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
6.7Red HatCVSS:3.1/AV:L/AC:L/PR:H/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

CWE-825Expired Pointer Dereference
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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