CVE-2026-90414: Linux kernel · IB/isert: reject PDUs declaring more data than was received
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 9.1 Critical.
Data as of 26 Oct 2026, 13:47 UTC
- EPSS
- 0.5% chance of exploitation in 30 days – higher than 43% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
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 17 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.
AI-suggested
A fix is available that validates the actual received byte length against the declared data segment length before processing PDUs, rejecting malformed PDUs and reinstating the connection if validation fails. Users should apply the official Linux kernel patches that address this issue. Since this is a kernel vulnerability, upgrading to a patched kernel version is the recommended remediation.
Description
A vulnerability in the Linux kernel's IB/isert component allows an attacker to cause an out-of-bounds read and potentially write unintended data to the backing store. This occurs because the code does not properly validate the declared data segment length against the actual received byte length in iSCSI PDUs, enabling an initiator to declare more data than was actually sent. The flaw can lead to heap corruption and denial of service. The issue has been resolved by adding proper length validation before processing PDUs.
References
- nvd.nist.gov/vuln/detail/CVE-2026-90414 (opens in a new tab)
- git.kernel.org/stable/c/274b1ad7e78338710864c4b4235bb1ce7e7107f9 (opens in a new tab)
- git.kernel.org/stable/c/2a6b8f88fb7ee51714a1922a039225bdcaf12855 (opens in a new tab)
- git.kernel.org/stable/c/352dc85324b29f5c85876f2666f3158b645e3f18 (opens in a new tab)
- git.kernel.org/stable/c/39da0b7e1f530347d284cebcfc5b5afa90a173bf (opens in a new tab)
- git.kernel.org/stable/c/957f92ea4022fb6af4618271615a2a21a7b5bef9 (opens in a new tab)
- git.kernel.org/stable/c/b4706722ed3ea72882b3c986a19b4a1ba66384c4 (opens in a new tab)
- git.kernel.org/stable/c/bc58e9d3dc560220c57b8bdfc12af0cff1c8a43d (opens in a new tab)
- git.kernel.org/stable/c/cf36fa5357a2fb25776a568d13a3653da7d99bcb (opens in a new tab)
- ubuntu.com/security/CVE-2026-90414 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-90414 (opens in a new tab)
- git.kernel.org/linus/957f92ea4022fb6af4618271615a2a21a7b5bef9 (opens in a new tab)