CVE-2026-68419: Linux kernel · RDMA/irdma: Prevent rereg_mr for non-mem regions
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.8 High · fixed in 7.0.0-38.38~24.04.4 : patch Linux kernel soon.
Data as of 26 Oct 2026, 13:47 UTC
- 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 7.0.0-38.38~24.04.4, 6.8.0-1036.39, 7.0.0-38.38 +12
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 10 Aug 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by 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
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.04 LTSlinuxpkg:deb/ubuntu/linux?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-gkepkg:deb/ubuntu/linux-gke?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
Description
In the Linux kernel, the following vulnerability has been resolved: RDMA/irdma: Prevent rereg_mr for non-mem regions When a QP/CQ/SRQ is created, a two step process is used where the buffer is allocated in userspace and explicitly registered with the normal reg_mr mechanism prior to creating the actual QP/CQ/SRQ object. These special registrations are indicated via an ABI field so the driver knows that they do not have a valid mkey and to skip the actual CQP command submission. Since these are real MR objects from the core's perspective, it is possible for a user application to invoke rereg_mr on them and cause a real CQP op to be emitted with the zero-initialized mkey value of 0. Fix this by preventing rereg_mr on these special regions.
References
- ubuntu.com/security/CVE-2026-68419 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-68419 (opens in a new tab)
- git.kernel.org/stable/c/ca1c29f05274b737dc964e28b97803750d7cf7ec (opens in a new tab)
- git.kernel.org/stable/c/b5029e91c63406e4f4c8d58161048b41b6f0bd8c (opens in a new tab)
- git.kernel.org/stable/c/fb46d134e1b8690bed2da9005b36d32d2efd34ac (opens in a new tab)
- git.kernel.org/stable/c/dbaa37e060918c45517786e37ecab0f300b48fa9 (opens in a new tab)
- git.kernel.org/stable/c/a846aecb931b4d65d5eafa92a0623545af46d4f2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8888-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8889-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8887-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8886-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8888-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8887-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8887-3 (opens in a new tab)