CVE-2026-93264: Linux kernel · RDMA/efa: Fix PBL chunk length computation
Affects Linux kernelSource GCVE Database
Not known to be exploited.
Data as of 26 Oct 2026, 13:47 UTC
Rated by Threat Radar · CVSS not yet scored by NVD
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 9% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Exploitation evidence
Disclosed: evidence found.
CVE published 24 Sep 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
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/efa: Fix PBL chunk length computation On register MR, when creating the PBL, if it's an indirect PBL we create a chunk list to hold the PBL pages pointers. Each chunk is 4KB in size and can hold 510 addresses (EFA_PTRS_PER_CHUNK) and has a 12-byte control buffer at the end of it holding the next chunk's pointer and its length. If the PBL number of pages is a multiple of EFA_PTRS_PER_CHUNK, the calculated last chunk length is wrongly computed as 0, even though that chunk is fully populated with 510 real page pointers. This wrong length is used both to DMA map the chunk and is propagated to the device, causing the device to see the chunk as empty and reject the memory registration. Fix the calculation so it will be performed only if the number of pages isn't a multiple of EFA_PTRS_PER_CHUNK, if it is, its already handled in the above loop correctly. Also prevent out-of-bounds reach in the chunks array in such scenario.
References
- ubuntu.com/security/CVE-2026-93264 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-93264 (opens in a new tab)
- git.kernel.org/stable/c/489b28f2377afa70c18c45b06a6387f3d39bb123 (opens in a new tab)
- git.kernel.org/stable/c/3982714e15512b83115897806dacc94899683420 (opens in a new tab)
- git.kernel.org/stable/c/665cd418b8561a099c3854443f8ad8ae751b72a0 (opens in a new tab)
- git.kernel.org/stable/c/1d4b5902773475fc97151379b7e5f09cad0fa57b (opens in a new tab)
- git.kernel.org/stable/c/932e5684906a090644a9061fae2d254041c3b8f2 (opens in a new tab)
- git.kernel.org/stable/c/229b42d7450c1cf96f45ec39ebb69211b06bc036 (opens in a new tab)
- git.kernel.org/stable/c/da7805f0211af19968584e621074f253ac07dba7 (opens in a new tab)
- git.kernel.org/stable/c/aadf3f9b5edb7f0a77e9172b237d2e07c754829c (opens in a new tab)
- msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-93264.json (opens in a new tab)
- support.microsoft.com/lifecycle (opens in a new tab)
- first.org/cvss (opens in a new tab)