{"id":"CVE-2026-48106","summary":"Arc Enterprise cluster replication accepts unauthenticated MsgReplicateSync messages, enabling cluster-wide data injection from any TLS-trusted peer","details":"Arc is an open, SQL-native time-series database for telemetry. Prior to version 26.06.1, Arc Enterprise's cluster replication receiver at `internal/cluster/replication/receiver.go` validates only the wire-format envelope (length, opcode) of inbound messages. The `MsgReplicateSync` payload itself is accepted without any application-layer authentication — no HMAC, no signature, no per-message nonce. The replication stream is protected at the transport layer by TLS / mTLS, but there is no protection against application-layer message tampering or replay once a peer is on the cluster network. This is fixed in 2026.06.1. Some workarounds are available. Restrict cluster network access to known-trusted peers via strict firewall rules, audit replication logs for unexpected `MsgReplicateSync` traffic, and/or disable cluster mode until the fix is available.","aliases":["GHSA-wfgr-8x84-22q7"],"modified":"2026-10-21T02:58:18.060058271Z","published":"2026-08-21T22:49:12.016Z","database_specific":{"cna_assigner":"GitHub_M","cwe_ids":["CWE-306","CWE-345","CWE-924"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/48xxx/CVE-2026-48106.json","unresolved_ranges":[{"extracted_events":[{"range":[{"fixed":"2026.06.1"}],"source":"AFFECTED_FIELD","strategy":"StringRangeExpression"}]},{"extracted_events":[{"range":[{"fixed":"2026.06.1"}],"source":"DESCRIPTION"}]}]},"references":[{"type":"ADVISORY","url":"https://github.com/Basekick-Labs/arc/security/advisories/GHSA-wfgr-8x84-22q7"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/48xxx/CVE-2026-48106.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-48106"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/basekick-labs/arc","events":[{"introduced":"0"},{"fixed":"8038f6f80f77bb48dbaa220e7415957be3988eff"}],"database_specific":{"extracted_events":[{"source":"DESCRIPTION","range":[{"introduced":"0"},{"fixed":"26.06.1"}]}]}}],"versions":["v26.05.1","v26.04.1","v26.03.2","v26.03.1","v26.02.2","v26.02.1","v26.01.2","v26.01.1","v25.12.1"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-48106.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:H/SA:N"}]}