Incorrect Authorization Affecting github.com/cilium/cilium/bpf package, versions <1.17.14>=1.18.0-pre.0 <1.18.8>=1.19.0-pre.0 <1.19.2
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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- published30 Mar 2026
- disclosed26 Mar 2026
- creditsudeephb, Champ-Goblem
Introduced: 26 Mar 2026
CVE-2026-33726 Â (opens in a new tab)How to fix?
Upgrade github.com/cilium/cilium/bpf to version 1.17.14, 1.18.8, 1.19.2 or higher.
Overview
Affected versions of this package are vulnerable to Incorrect Authorization through the cil_to_container and bpf_lxc local-backend packet path in the datapath components. An attacker can bypass ingress network policies and reach a local backend pod by sending traffic through an L7 load balancer when per-endpoint routing is enabled, and BPF host routing is disabled.
Notes
- The bypass affects traffic from pods to L7 Services (Envoy/GAMMA) when the selected backend is local to the same node.
- The issue is most relevant in deployments where per-endpoint routes are enabled automatically, such as Cilium ENI on EKS and other cloud-IPAM-based setups.
- Without the fix, packets handled on the backend pod ingress path could return
CTX_ACT_OKbefore ingress policy enforcement, skipping the expected policy check.