nebula-mesh CVE-2026-48025

Exploitation requires local memory-read access to the nebula-mesh server process on the host where it runs. Specific vectors include: attaching via ptrace (requires CAP_SYS_PTRACE or ptrace_scope permitting it), generating or intercepting a core dump, accessing a container or VM memory snapshot (e.g., via cloud provider snapshot APIs or hypervisor access), obtaining an OOM kill debug bundle, or exploiting shared CPU cache-line side channels. The vulnerability is triggered by any invocation of the enrollment, update, or mobile bundle API endpoints, which cause the plaintext key to be written to heap. The key persists until Go's GC scavenges the slice - minutes to hours under load, potentially indefinitely on idle servers. There is no remote network exploitation path; the host or container boundary must first be crossed. Exploitation is additionally constrained by the requirement that the attacker can read arbitrary process heap memory, not merely user-space file access.

No CVSS vector or EPSS score is available for this CVE, so quantitative risk scoring cannot be applied. The vulnerability is not listed in CISA KEV and no public exploit code has been identified. The attack vector is strictly local: exploitation requires memory-read access to the server process via ptrace, core dump, container or VM snapshot, kernel swap artifacts, or OOM debug bundles. This significantly constrains the attack surface relative to typical network-exploitable vulnerabilities. However, the impact is disproportionately severe - successful exploitation yields the CA's ed25519 private key, enabling arbitrary certificate forgery and complete compromise of the PKI trust chain. The gap between low exploitability (local access required) and catastrophic impact (CA key compromise) makes this a high-priority fix for any deployment where the host is not fully isolated, including containerized or multi-tenant environments where snapshot or memory-inspection primitives may be accessible to co-tenants or operators.

An attacker or malicious insider with local access to the host running nebula-mesh - or a co-tenant in a shared container environment with access to snapshot primitives - triggers or waits for any enrollment or certificate-signing operation, then captures a core dump or reads /proc/<pid>/mem to scan heap memory for the 64-byte ed25519 private key pattern. Because the key may persist for minutes to hours (or indefinitely on idle servers), a narrow timing window is not required. With the extracted key, the attacker can forge arbitrary CA-signed certificates, fully compromising the mesh PKI. No public exploit code has been identified at time of analysis.