Bug 2529684 (CVE-2026-86566)

Summary: CVE-2026-86566 dpdk: dpdk: Guest with runt RX descriptors underflows copy length in vhost enqueue (split and packed rings)
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, echaudro, eglynn, fleitner, jdelft, jjoyce, jpretori, jschluet, jupierce, ktraynor, lgarciaa, lhh, mbiarnes, mburns, mgarciac, ppalepu, ppostler, prdhamdh, rhel-process-autobot, rkhan, security-response-team, sfaye, sghai, sidsharm, suppawar, vlaad, watson-tool-maintainers
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
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Fixed In Version: Doc Type: ---
Doc Text:
A flaw was found in DPDK lib/vhost. A guest with runt RX descriptors can underflow the copy length in vhost enqueue, causing a denial of service in a shared vhost backend such as OVS-DPDK.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On: 2552424, 2552425    
Bug Blocks:    
Deadline: 2026-12-08   

Description OSIDB Bzimport 2026-09-08 02:47:02 UTC
A flaw was found in DPDK lib/vhost. Runt RX descriptors underflow the copy length in vhost enqueue on both split and packed rings. Unsigned subtraction underflow allows a full packet copy past a tiny descriptor window, which can crash a host vswitch such as OVS-DPDK.