CVE-2026-64269: Linux kernel · RDMA/rtrs-srv: Bound RDMA-Write length to chunk size in rdma_write_sg
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 9.1 Critical · fixed in 5.15.0-1117.124~20.04.1 : patch Linux kernel as a priority.
Data as of 26 Oct 2026, 14:05 UTC
- EPSS
- 0.7% chance of exploitation in 30 days – higher than 53% 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 +44
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 25 Jul 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
An official fix is available and should be applied promptly. The patch bounds the RDMA-Write length to the chunk size, preventing out-of-bounds reads. Users should update to patched Linux kernel versions as per the vendor advisory. No additional mitigations are required beyond applying the official update.
Description
A vulnerability in the Linux kernel's RDMA subsystem (CVE-2026-64269) allowed a remote peer to specify an RDMA-Write length exceeding the allowed chunk size, potentially causing out-of-bounds reads. This could lead to disclosure of adjacent host memory or connection aborts depending on IOMMU configuration. The issue was fixed by bounding the RDMA-Write length to the chunk size. The vulnerability affects multiple Linux kernel versions prior to 7.0.0-31.31 and related builds. A high severity CVSS 3.1 score of 9.1 is assigned. Official patches are available from the vendor.
References
- nvd.nist.gov/vuln/detail/CVE-2026-64269 (opens in a new tab)
- git.kernel.org/stable/c/2912f3d40355dabc08fdbaaf2764d02445fe88dc (opens in a new tab)
- git.kernel.org/stable/c/5a45d0aa1fa50a333ce5763ade744e2d89838667 (opens in a new tab)
- git.kernel.org/stable/c/68c09762172f6224e9ddf9b0a60bacbb36e443eb (opens in a new tab)
- git.kernel.org/stable/c/6cada540150894e81042a0ae0c796a21a9a877da (opens in a new tab)
- git.kernel.org/stable/c/6f40246f4312fdbab5a13cc440adebf95eb2aa66 (opens in a new tab)
- git.kernel.org/stable/c/963af8d97a8c6a117134a8d0db1415e0489200b1 (opens in a new tab)
- git.kernel.org/stable/c/da3e44add94b05dfde56f898421922f5cf35705f (opens in a new tab)
- ubuntu.com/security/CVE-2026-64269 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-64269 (opens in a new tab)
- git.kernel.org/linus/963af8d97a8c6a117134a8d0db1415e0489200b1 (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)
- ubuntu.com/security/notices/USN-8728-2 (opens in a new tab)