Bug 2536161 (CVE-2026-90230)

Summary: CVE-2026-90230 kernel: nvmet: fix heap out-of-bounds read in nvmet_auth_negotiate()
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: akhatavk, aos-team-art-private, asdas, dpaolell, jdelft, jupierce, lgarciaa, mbiarnes, ppalepu, ppostler, prdhamdh, rhel-process-autobot, sghai, sidsharm, suppawar, vlaad, watson-tool-maintainers
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
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Doc Text:
A flaw was found in the Linux kernel's `nvmet` subsystem. A remote attacker, by sending a specially crafted NVMe-oF (NVMe over Fabrics) in-band authentication negotiation message with an invalid transfer length or identifier lengths, could trigger a heap out-of-bounds read in the `nvmet_auth_negotiate()` function. This vulnerability could lead to information disclosure or a denial of service.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-09-17 16:41:03 UTC 
In the Linux kernel, the following vulnerability has been resolved:

nvmet: fix heap out-of-bounds read in nvmet_auth_negotiate()

nvmet_execute_auth_send() allocates the DH-HMAC-CHAP message buffer with
the host-supplied transfer length (tl) and hands it to
nvmet_auth_negotiate() without passing tl along. nvmet_auth_negotiate()
then reads the negotiate header and, for each of the halen hash
identifiers and dhlen DH group identifiers, indexes into the fixed
idlist[60] array (hashes at idlist[0..halen), groups at idlist[30..]).

Neither the transfer length nor halen/dhlen is validated. A malicious or
non-conformant host can report a tl smaller than the negotiate structure,
or a halen/dhlen larger than the array (both are u8, up to 255), making
the loops read past the end of the allocated buffer (heap out-of-bounds
read). The sibling nvmet_auth_reply() already validates tl against the
structure size; the negotiate path did not.

Pass tl into nvmet_auth_negotiate(), reject a tl that does not cover the
negotiate data plus one full protocol descriptor, and reject halen/dhlen
larger than NVME_AUTH_DHCHAP_MAX_DH_IDS.
Comment 1 Mauro Matteo Cascella 2026-09-24 15:01:37 UTC 
Upstream advisory:
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-90230.mbox