Skip to main content
VulnerabilityPublished Updated

CVE-2026-98253: Linux kernel · RDMA/ucma: Serialize join and leave on copy_to_user failure

Affects Linux kernelSource CVE Database V5

0

Not known to be exploited · CVSS 7.8 High · fixed in ae805d204cf1f15b87d1bf3529b4c649f3519420 : patch Linux kernel soon.

Data as of 26 Oct 2026, 14:05 UTC

CVSS 3.1 base score
7.8High
How severe the flaw is on the 0–10 CVSS scale.
EPSS
0.1% chance of exploitation in 30 days – higher than 2% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch
Available – fixed in ae805d204cf1f15b87d1bf3529b4c649f3519420, 83610ee5e498fa5bfcb80031d2b959baea276bf6, 52172e11bd074ccaded21740ffeb67123f01dd00 +7
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Exploitation evidence

  1. Disclosed: evidence found.

    CVE published 6 Oct 2026

  2. Detectable: no evidence on record.

    No public nuclei template indexed

  3. Weaponised: no evidence on record.

    No public exploit code indexed in Metasploit or Exploit-DB

  4. Exploited in the wild: no evidence on record.

    Not in CISA KEV and no source reports exploitation

  5. Observed by OffSeq Mirage: no evidence on record.

    No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

What to do

Upgrade to a fixed release listed under Affected software.

Affected software

ProductAffectedFixed in
LinuxLinuxAffected
  • >=5.10.20 <5.10.271
  • >=5.11.3 <5.12
Fixed in
  • ae805d204cf1f15b87d1bf3529b4c649f3519420
  • 83610ee5e498fa5bfcb80031d2b959baea276bf6
  • 52172e11bd074ccaded21740ffeb67123f01dd00
  • 662ade4de9ff5eceb0820a9f8e9fac70ba6a815b
  • 43c4e24bd10370fc976f6220518049ce71419399
  • 29b9ed83d8bfab5c6e11fcbf1aa836aa4ae26cb9
  • 5.12
  • 5.10.271
  • 01e29d0d78a8f66f221625720a04939eef5ec1f6
  • 01cbdb724c584d7772fd25af2e4dfdf8527ce0d5
LinuxLinuxAffected
  • =5.12
Fixed in–

AI-suggested

This vulnerability has been fixed in Linux kernel versions 5.10.271, 5.12, and later. Users and administrators should update to these fixed versions to remediate the issue. No additional mitigations are indicated by the vendor advisory.

Description

CVE-2026-98253 is a high-severity vulnerability in the Linux kernel's RDMA/ucma subsystem. It involves a race condition between concurrent multicast join and leave operations that can lead to use-after-free of kernel memory. The flaw arises from improper serialization of join and leave calls when copy_to_user() fails, potentially causing kernel memory corruption and impacting confidentiality, integrity, and availability.

References

Community reviews

Loading reviews…