CVE-2026-63865

Kernel crash or corruption via sleepable hooks

Published Jul 19, 2026 · Updated Jul 19, 2026

Concurrent-context misuse in the Linux Kernel allows local users to crash or corrupt the host kernel via a sleepable BPF LSM program. bpf_lsm_task_to_inode runs under rcu_read_lock and bpf_lsm_inet_conn_established runs in softirq context, yet both were advertised to sleepable programs. Reachability requires CONFIG_BPF_LSM and privileges to load and attach a sleepable BPF LSM program; triggering either hook can panic the host or corrupt kernel state.

CVSS severity8.8
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

Concurrent-context misuse in the Linux Kernel allows local users to crash or corrupt the host kernel via a sleepable BPF LSM program. bpf_lsm_task_to_inode runs under rcu_read_lock and bpf_lsm_inet_conn_established runs in softirq context, yet both were advertised to sleepable programs. Reachability requires CONFIG_BPF_LSM and privileges to load and attach a sleepable BPF LSM program; triggering either hook can panic the host or corrupt kernel state.

The record

CVE
CVE-2026-63865
Published
Jul 19, 2026
Updated
Jul 19, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
CWE-663, T1499.004
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=423f16108c9d832bd96059d5c882c8ef6d76eb96 <0d918263c9bfc86078edb2e2f7302a0c6ce42b7c
  2. Affected versionversion=423f16108c9d832bd96059d5c882c8ef6d76eb96 <26b380a3ca0b605fd8860995ed6a208f276dd316
  3. Affected versionversion=423f16108c9d832bd96059d5c882c8ef6d76eb96 <281f2a214565a5cbf8b7355a65738d80bd19b8c5
  4. Affected versionversion=423f16108c9d832bd96059d5c882c8ef6d76eb96 <452a927cddcd67478d030e646f41cb904a93156f
  5. Affected versionversion=423f16108c9d832bd96059d5c882c8ef6d76eb96 <989f1b93907de1753a814996222da375f07e579b
  6. Affected versionversion=423f16108c9d832bd96059d5c882c8ef6d76eb96 <beaf0e96b1da74549a6cabd040f9667d83b2e97e
  7. Affected versionversion=423f16108c9d832bd96059d5c882c8ef6d76eb96 <f0fc2a9828171205244a28013f02889f50b71c9f
  8. Affected versionversion=5.11

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=423f16108c9d832bd96059d5c882c8ef6d76eb96 <0d918263c9bfc86078edb2e2f7302a0c6ce42b7c; version=423f16108c9d832bd96059d5c882c8ef6d76eb96 <26b380a3ca0b605fd8860995ed6a208f276dd316; version=423f16108c9d832bd96059d5c882c8ef6d76eb96 <281f2a214565a5cbf8b7355a65738d80bd19b8c5; version=423f16108c9d832bd96059d5c882c8ef6d76eb96 <452a927cddcd67478d030e646f41cb904a93156f; version=423f16108c9d832bd96059d5c882c8ef6d76eb96 <989f1b93907de1753a814996222da375f07e579b; version=423f16108c9d832bd96059d5c882c8ef6d76eb96 <beaf0e96b1da74549a6cabd040f9667d83b2e97e; version=423f16108c9d832bd96059d5c882c8ef6d76eb96 <f0fc2a9828171205244a28013f02889f50b71c9f; version=5.11

Published CVSS scores

5.5Red HatCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
8.8kernel.orgCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/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-663Use of a Non-reentrant Function in a Concurrent Context
T1499.004Application or System Exploitation

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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