CVE-2026-64281Network attack vector

Remote service hang via missed transport-close wakeup

Published Jul 25, 2026 · Updated Jul 25, 2026

Denial of service in Linux Kernel 7.1 allows remote attackers to hang NFS/RDMA service workers via crafted RPC/RDMA traffic. The svcrdma close paths set XPT_CLOSE without waking sc_sq_ticket_wait and sc_send_wait, so threads in svc_rdma_sq_wait retain transport references and block svc_rdma_free. An unauthenticated peer must reach a listening NFS/RDMA server and create send-queue pressure before disconnecting; parked workers can then halt the service and teardown.

CVSS severity7.5
High
EPSS probability0.47%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Denial of service in Linux Kernel 7.1 allows remote attackers to hang NFS/RDMA service workers via crafted RPC/RDMA traffic. The svcrdma close paths set XPT_CLOSE without waking sc_sq_ticket_wait and sc_send_wait, so threads in svc_rdma_sq_wait retain transport references and block svc_rdma_free. An unauthenticated peer must reach a listening NFS/RDMA server and create send-queue pressure before disconnecting; parked workers can then halt the service and teardown.

The record

CVE
CVE-2026-64281
Published
Jul 25, 2026
Updated
Jul 25, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
CWE-772, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 25, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 25, 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=7.1
  2. Affected versionversion=ccc89b9d1ed233349cfe8d87b842e7351b74d8de <40eedc4253dbda0b29b7961200534dfcecb48ace
  3. Affected versionversion=ccc89b9d1ed233349cfe8d87b842e7351b74d8de <e5248a7426030db1e126363f72afdb3b71339a5c

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=7.1; version=ccc89b9d1ed233349cfe8d87b842e7351b74d8de <40eedc4253dbda0b29b7961200534dfcecb48ace; version=ccc89b9d1ed233349cfe8d87b842e7351b74d8de <e5248a7426030db1e126363f72afdb3b71339a5c

Published CVSS scores

5.5Red HatCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
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.

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

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-772Missing Release of Resource after Effective Lifetime
T1499.004Endpoint Denial of Service: Application 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

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo