CVE-2026-48106

Arc Enterprise cluster replication accepts unauthenticated MsgReplicateSync messages, enabling cluster-wide data injection from any TLS-trusted peer

Published Aug 21, 2026 CVSS 4.0 · 8.3 High EPSS < 1% KEV · Not listed
Description
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Basekick-labs
Basekick-labs arc
Vendors & Products Basekick-labs
Basekick-labs arc
Type Values Removed Values Added
Description 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.
Title Arc Enterprise cluster replication accepts unauthenticated MsgReplicateSync messages, enabling cluster-wide data injection from any TLS-trusted peer
Weaknesses CWE-306
CWE-345
CWE-924
References
Metrics cvssV4_0

{'score': 8.3, 'vector': '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'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Aug 26, 2026, 5:47 PM
Reserved
May 20, 2026, 6:46 PM
Status
Deferred
Published
Aug 21, 2026, 11:16 PM
Modified
Oct 12, 2026, 4:10 PM