CVE-2026-46135

Published May 28, 2026

Last updated 6 days ago

CVSS critical 9.8

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: nvmet-tcp: fix race between ICReq handling and queue teardown nvmet_tcp_handle_icreq() updates queue->state after sending an Initialization Connection Response (ICResp), but it does so without serializing against target-side queue teardown. If an NVMe/TCP host sends an Initialization Connection Request (ICReq) and immediately closes the connection, target-side teardown may start in softirq context before io_work drains the already buffered ICReq. In that case, nvmet_tcp_schedule_release_queue() sets queue->state to NVMET_TCP_Q_DISCONNECTING and drops the queue reference under state_lock. If io_work later processes that ICReq, nvmet_tcp_handle_icreq() can still overwrite the state back to NVMET_TCP_Q_LIVE. That defeats the DISCONNECTING-state guard in nvmet_tcp_schedule_release_queue() and allows a later socket state change to re-enter teardown and issue a second kref_put() on an already released queue. The ICResp send failure path has the same problem. If teardown has already moved the queue to DISCONNECTING, a send error can still overwrite the state with NVMET_TCP_Q_FAILED, again reopening the window for a second teardown path to drop the queue reference. Fix this by serializing both post-send state transitions with state_lock and bailing out if teardown has already started. Use -ESHUTDOWN as an internal sentinel for that bail-out path rather than propagating it as a transport error like -ECONNRESET. Keep nvmet_tcp_socket_error() setting rcv_state to NVMET_TCP_RECV_ERR before honoring that sentinel so receive-side parsing stays quiesced until the existing release path completes.
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Undergoing Analysis
Products
linux_kernel

Risk scores

CVSS 3.1

Type
Secondary
Base score
9.8
Impact score
5.9
Exploitability score
3.9
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Severity
CRITICAL

Weaknesses

nvd@nist.gov
CWE-362

Social media

Hype score
Not currently trending

  1. CVE-2026-46135: Critical (9.8) race condition in the Linux kernel's nvmet-tcp. ICReq handling vs queue teardown can be exploited remotely with no auth required. No interaction needed. Patch your kernel. #Linux #CVE https://t.co/ROSS12nEem https://t.co/vhu7m1RmgH

    @SecAlertsCo

    4 Jun 2026

    55 Impressions

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  2. 🪟 CVE-2026-46135 is the “Windows admin, now learn Linux plumbing” plot twist. If MSRC pages are MIA, you’re basically triaging from kernel threads—fun… until it isn’t. #Windows #Security #Linux #Storage #CVE https://t.co/Y07moNiYC8 #LinuxSecurity #NvmetTcp #Cve2026

    @windowsforum

    29 May 2026

    65 Impressions

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Configurations

Related CVEs

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References

Sources include official advisories and independent security research.