CVE-2026-46043Network attack vector

Kernel-memory disclosure or crash via length underflow

Published May 27, 2026 · Updated May 27, 2026

Integer underflow in the RDMA RXE receive path in Linux Kernel allows remote attackers to read kernel memory or crash systems via RoCEv2. rxe_rcv checks only the fixed-header length before payload_size subtracts the attacker-controlled BTH pad and ICRC size, allowing the result to underflow. No privileges or user interaction are required; successful exploitation can expose kernel memory or interrupt the system through a kernel crash.

CVSS severity9.1
Critical
EPSS probability0.51%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Integer underflow in the RDMA RXE receive path in Linux Kernel allows remote attackers to read kernel memory or crash systems via RoCEv2. rxe_rcv checks only the fixed-header length before payload_size subtracts the attacker-controlled BTH pad and ICRC size, allowing the result to underflow. No privileges or user interaction are required; successful exploitation can expose kernel memory or interrupt the system through a kernel crash.

The record

CVE
CVE-2026-46043
Published
May 27, 2026
Updated
May 27, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 27, 2026CVE publishedPublication date reported by the CVE source.
  2. May 27, 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=4.8
  2. Affected versionversion=8700e3e7c4857d28ebaa824509934556da0b3e76 <2fd4f8b749309a61c3f3f88ee8891d94f79e1240
  3. Affected versionversion=8700e3e7c4857d28ebaa824509934556da0b3e76 <7244491dab347f648e661da96dc0febadd9daec3
  4. Affected versionversion=8700e3e7c4857d28ebaa824509934556da0b3e76 <9b924f3a26b21330a837cfe72e819b6393bbeeaa
  5. Affected versionversion=8700e3e7c4857d28ebaa824509934556da0b3e76 <e8ee0e792d475b1067c199ef0af1b6221fa6f43d
  6. Affected versionversion=8700e3e7c4857d28ebaa824509934556da0b3e76 <f83519a4c122c9c7a850a2197648a9ff4c67c520

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=4.8; version=8700e3e7c4857d28ebaa824509934556da0b3e76 <2fd4f8b749309a61c3f3f88ee8891d94f79e1240; version=8700e3e7c4857d28ebaa824509934556da0b3e76 <7244491dab347f648e661da96dc0febadd9daec3; version=8700e3e7c4857d28ebaa824509934556da0b3e76 <9b924f3a26b21330a837cfe72e819b6393bbeeaa; version=8700e3e7c4857d28ebaa824509934556da0b3e76 <e8ee0e792d475b1067c199ef0af1b6221fa6f43d; version=8700e3e7c4857d28ebaa824509934556da0b3e76 <f83519a4c122c9c7a850a2197648a9ff4c67c520

Published CVSS scores

9.1kernel.orgCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/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.

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)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499.004Endpoint Denial of Service: Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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