CVE-2026-43199Network attack vector

Service interruption via sleeping atomic-context MAC query

Published May 6, 2026 · Updated May 6, 2026

Improper atomic-context scheduling in Linux Kernel allows remote attackers to interrupt service through mlx5e IPsec event handling. The mlx5e_ipsec_init_macs function queries hardware through mlx5_cmd_exec, which can sleep, while mlx5e_ipsec_handle_event runs in atomic context. Reachability requires the mlx5e IPsec offload path, and the scheduling violation affects availability without reported data exposure or modification.

CVSS severity7.5
High
EPSS probability0.44%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper atomic-context scheduling in Linux Kernel allows remote attackers to interrupt service through mlx5e IPsec event handling. The mlx5e_ipsec_init_macs function queries hardware through mlx5_cmd_exec, which can sleep, while mlx5e_ipsec_handle_event runs in atomic context. Reachability requires the mlx5e IPsec offload path, and the scheduling violation affects availability without reported data exposure or modification.

The record

CVE
CVE-2026-43199
Published
May 6, 2026
Updated
May 6, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
T1499
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 6, 2026CVE publishedPublication date reported by the CVE source.
  2. May 6, 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=6.2
  2. Affected versionversion=cee137a634318bfbda18ee5af45d300153b57fa5 <546de94e41e92e1f7dc6213615fb7c794d05db98
  3. Affected versionversion=cee137a634318bfbda18ee5af45d300153b57fa5 <57957bc7f1865778ec9b1618e15515feb6df7eb4
  4. Affected versionversion=cee137a634318bfbda18ee5af45d300153b57fa5 <859380694f434597407632c29f30fdb5e763e6cc
  5. Affected versionversion=cee137a634318bfbda18ee5af45d300153b57fa5 <e1407fb7c337373dfaaae2445d828b0b9ae26a29

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=6.2; version=cee137a634318bfbda18ee5af45d300153b57fa5 <546de94e41e92e1f7dc6213615fb7c794d05db98; version=cee137a634318bfbda18ee5af45d300153b57fa5 <57957bc7f1865778ec9b1618e15515feb6df7eb4; version=cee137a634318bfbda18ee5af45d300153b57fa5 <859380694f434597407632c29f30fdb5e763e6cc; version=cee137a634318bfbda18ee5af45d300153b57fa5 <e1407fb7c337373dfaaae2445d828b0b9ae26a29

Published CVSS scores

7.5kernel.orgCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499Endpoint Denial of Service

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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