CVE-2012-5573: The connection_edge_process_relay_cell function in or/relay.c in Tor before 0.2.3.25 maintains circuits eve...

Security readout for executives and security teams

CVE-2012-5573 is a Tor denial-of-service issue fixed in Tor 0.2.3.25. A remote attacker could send unexpected flow-control messages that Tor failed to handle safely, potentially causing memory pressure, excessive traffic handling, or bypassing intended flow-control limits. Exposure is mainly systems running Tor versions earlier than 0.2.3.25, including packaged Tor deployments from affected Linux distributions. The provided affected-product metadata is sparse, so confirm exposure through local package and binary version inventory. Treat this as a targeted remediation item for any Tor infrastructure. It is not supported by active-exploitation evidence in the bundle, but the remote denial-of-service impact can affect availability and operational reliability. Mitigation focus: Upgrade Tor to 0.2.3.25 or a later supported release.; Apply distribution security updates from vendors such as Gentoo or Red Hat where applicable.; Prioritize internet-facing Tor relay, bridge, and service hosts for remediation..

Prepared

Jun 24, 2026, 12:04 UTC (UTC+00:00)

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.