CVE-2026-90309Hinoki check available

Local privilege escalation via ERDMA CQ use-after-free

Published Sep 17, 2026 · Updated Sep 18, 2026

Use-after-free in Linux kernel 6.0 and later affected branches allows local users to escalate privileges through ERDMA CQ teardown. erdma_destroy_cq removes and frees a completion queue while scheduled EQ handlers can still dereference it and invoke freed callback pointers. Exploitation requires access to an ERDMA uverbs device and an attacker-controlled race between locally generated CQ events and destruction, enabling kernel control-flow hijacking or a host panic.

CVSS severity7.8
High
EPSS probability0.17%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Use-after-free in Linux kernel 6.0 and later affected branches allows local users to escalate privileges through ERDMA CQ teardown. erdma_destroy_cq removes and frees a completion queue while scheduled EQ handlers can still dereference it and invoke freed callback pointers. Exploitation requires access to an ERDMA uverbs device and an attacker-controlled race between locally generated CQ events and destruction, enabling kernel control-flow hijacking or a host panic.

The record

CVE
CVE-2026-90309
Published
Sep 17, 2026
Updated
Sep 18, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
CWE-416, T1068
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 17, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 18, 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=155055771704f8cbb5c176a4309b7dc30a50450c <05b8ca493dd02319bca93c640b259c2ba51ef321
  2. Affected versionversion=155055771704f8cbb5c176a4309b7dc30a50450c <1fc9c1933959d2776a1ce7bf424251b8b5b586cd
  3. Affected versionversion=155055771704f8cbb5c176a4309b7dc30a50450c <4545f355654d044d35a31cd01cc46f491a8a7c36
  4. Affected versionversion=155055771704f8cbb5c176a4309b7dc30a50450c <610ef81797bb4f709e8675c1d8d093bb9ccdcbd8
  5. Affected versionversion=155055771704f8cbb5c176a4309b7dc30a50450c <98df2aee1459ee1c62c70cbe9b370d2a532aea36
  6. Affected versionversion=155055771704f8cbb5c176a4309b7dc30a50450c <c0a83f29a24c7e7f8516630848ef6db4c174deed
  7. Affected versionversion=6.0

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=155055771704f8cbb5c176a4309b7dc30a50450c <05b8ca493dd02319bca93c640b259c2ba51ef321; version=155055771704f8cbb5c176a4309b7dc30a50450c <1fc9c1933959d2776a1ce7bf424251b8b5b586cd; version=155055771704f8cbb5c176a4309b7dc30a50450c <4545f355654d044d35a31cd01cc46f491a8a7c36; version=155055771704f8cbb5c176a4309b7dc30a50450c <610ef81797bb4f709e8675c1d8d093bb9ccdcbd8; version=155055771704f8cbb5c176a4309b7dc30a50450c <98df2aee1459ee1c62c70cbe9b370d2a532aea36; version=155055771704f8cbb5c176a4309b7dc30a50450c <c0a83f29a24c7e7f8516630848ef6db4c174deed; version=6.0

Published CVSS scores

7.8Linux kernel CVE teamCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
7.0Amazon LinuxCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/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.

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

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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

CWE-416Use After Free
T1068Exploitation for Privilege Escalation

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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