CVE-2026-53133: Linux kernel · RDMA/umem: Fix truncation for block sizes >= 4G
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.8 High · fixed in 5.15.0-1117.124~20.04.1 : 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 5.15.0-1117.124~20.04.1, 5.15.0-1123.132~20.04.1, 5.15.0-1122.131~20.04.1 +69
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 25 Jun 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.
AI-suggested
A fix is available and included in Linux kernel versions 5.15.0-1111.115~20.04.1 and later. Users should update to these or newer kernel versions to remediate the vulnerability. No additional mitigations are indicated by the vendor advisory.
Description
A vulnerability in the Linux kernel's RDMA/umem subsystem caused incorrect DMA address calculations for block sizes of 4GB or larger when using iommu, due to 32-bit value truncation. This flaw could lead to memory corruption or other impacts related to incorrect DMA operations. The issue has been fixed in Linux kernel versions 5.15.0-1111.115~20.04.1 and later. The vulnerability has a CVSS score of 7.8, indicating a medium severity level. No known exploits in the wild have been reported. Users should apply the official kernel updates to remediate this issue.
References
- ubuntu.com/security/CVE-2026-53133 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-53133 (opens in a new tab)
- git.kernel.org/linus/15fe76e23615f502d051ef0768f86babaf08746c (opens in a new tab)
- git.kernel.org/stable/c/15fe76e23615f502d051ef0768f86babaf08746c (opens in a new tab)
- git.kernel.org/stable/c/2ff4b7817e5b78070c30f5fb5e678e452a2628b3 (opens in a new tab)
- git.kernel.org/stable/c/8fe0231adebe086c8a459c790944ac026cd99c6e (opens in a new tab)
- git.kernel.org/stable/c/ac1aad8e1281534ce936c250f68084fc79c5469e (opens in a new tab)
- git.kernel.org/stable/c/afd35fec9297195b759078745549c2671223f24f (opens in a new tab)
- git.kernel.org/stable/c/baf8685bcf56dc1efb44b8f6a57c42516e549068 (opens in a new tab)
- git.kernel.org/stable/c/cc644d5608e3b0dadc970bd6e6aa26b91ea07d0f (opens in a new tab)
- git.kernel.org/stable/c/dee2a49adeeb2a5e16a3fc858fa21b841c519802 (opens in a new tab)
- ubuntu.com/security/notices/USN-8726-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8727-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8728-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8760-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8781-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8726-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8726-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-8800-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8760-2 (opens in a new tab)