Bug 2441217 (CVE-2026-26963)

Summary: CVE-2026-26963 cilium: Cilium: Information disclosure via incorrect traffic permitting with specific network configurations
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: adudiak, alcohan, fdeutsch, gparvin, jbalunas, kshier, oramraz, pahickey, rhaigner, smullick, stcannon, stirabos, teagle, thason, yguenane
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in Cilium. When specific network configurations, including Native Routing, WireGuard, and Node Encryption, are enabled, Cilium incorrectly allows network traffic from Pods on other nodes. This can lead to unauthorized access to network communications and potential information disclosure.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-02-20 00:02:13 UTC
Cilium is a networking, observability, and security solution with an eBPF-based dataplane. Versions 1.18.0 through 1.18.5 will incorrectly permit traffic from Pods on other nodes when Native Routing, WireGuard and Node Encryption are enabled. This issue has been fixed in version 1.18.6.