CVE-2026-93222

Signal sender misattribution via shared siginfo rewrite

Published Sep 24, 2026 · Updated Sep 24, 2026

Improper signal metadata handling in Linux allows local users to make later group recipients receive incorrect sender IDs across namespaces. send_signal_locked() rewrites sender PID and UID values in a shared siginfo object for each target namespace instead of copying the object before mutation. Reachability requires a permitted group signal that crosses namespace boundaries; the bounded consequence is incorrect sender attribution in recipient signal metadata.

CVSS severityUnavailable
Unscored
EPSS probability0.18%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper signal metadata handling in Linux allows local users to make later group recipients receive incorrect sender IDs across namespaces. send_signal_locked() rewrites sender PID and UID values in a shared siginfo object for each target namespace instead of copying the object before mutation. Reachability requires a permitted group signal that crosses namespace boundaries; the bounded consequence is incorrect sender attribution in recipient signal metadata.

The record

CVE
CVE-2026-93222
Published
Sep 24, 2026
Updated
Sep 24, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
Unavailable
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 24, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 24, 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=2f0e9eed11ca778d0ec5507a739c28472fd4ca20
  2. Affected versionversion=5.1.20 <5.2
  3. Affected versionversion=5.2.3 <5.3
  4. Affected versionversion=5.3
  5. Affected versionversion=7a0cf094944e2540758b7f957eb6846d5126f535 <03c8761e75d1619906bb503686f9cc1dfc6a67f4
  6. Affected versionversion=7a0cf094944e2540758b7f957eb6846d5126f535 <148b0dae2a1755beb873a2aab51fb191414f068c
  7. Affected versionversion=7a0cf094944e2540758b7f957eb6846d5126f535 <4ee7c4e4719a825052f42f02ec159b5b42b68fbc
  8. Affected versionversion=7a0cf094944e2540758b7f957eb6846d5126f535 <6b1de022304ef85284c5933a5fb8492f6f54efc9
  9. Affected versionversion=7a0cf094944e2540758b7f957eb6846d5126f535 <a246da20c8e4ae4319511c698b9f26ad0ad1769f
  10. Affected versionversion=7a0cf094944e2540758b7f957eb6846d5126f535 <b655c2040ce836afad5643842543567b31f8c11d
  11. Affected versionversion=7a0cf094944e2540758b7f957eb6846d5126f535 <d19cdc167e696714509e87d3f7ae765b6e164589
  12. Affected versionversion=7a0cf094944e2540758b7f957eb6846d5126f535 <e015d1ac6b43a23c52c5163299414ae77d7d4ae0
  13. Affected versionversion=e897dd22800f02bd48aefb1511fff0b2ce96e94c

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=2f0e9eed11ca778d0ec5507a739c28472fd4ca20; version=5.1.20 <5.2; version=5.2.3 <5.3; version=5.3; version=7a0cf094944e2540758b7f957eb6846d5126f535 <03c8761e75d1619906bb503686f9cc1dfc6a67f4; version=7a0cf094944e2540758b7f957eb6846d5126f535 <148b0dae2a1755beb873a2aab51fb191414f068c; version=7a0cf094944e2540758b7f957eb6846d5126f535 <4ee7c4e4719a825052f42f02ec159b5b42b68fbc; version=7a0cf094944e2540758b7f957eb6846d5126f535 <6b1de022304ef85284c5933a5fb8492f6f54efc9; version=7a0cf094944e2540758b7f957eb6846d5126f535 <a246da20c8e4ae4319511c698b9f26ad0ad1769f; version=7a0cf094944e2540758b7f957eb6846d5126f535 <b655c2040ce836afad5643842543567b31f8c11d; version=7a0cf094944e2540758b7f957eb6846d5126f535 <d19cdc167e696714509e87d3f7ae765b6e164589; version=7a0cf094944e2540758b7f957eb6846d5126f535 <e015d1ac6b43a23c52c5163299414ae77d7d4ae0; version=e897dd22800f02bd48aefb1511fff0b2ce96e94c

Published CVSS scores

No CVSS assessment is available in this record.

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.

Activity data is delayed. The latest report is Sep 28, 2026.

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

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

No sourced classifications are available.

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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