{"id":"CVE-2026-93424","title":"FastNetMon: NetFlow/IPFIX template cache returns unlocked pointers, causing heap-use-after-free on multi-port deployments","summary":"FastNetMon is a high-performance DDoS detector and sensor. In version 1.2.9 and earlier, peer_find_template() in src/netflow_plugin/netflow_collector.cpp and src/netflow_plugin/netflow_v9_collector.cpp returns a pointer into global_netfl…","severity":"high","cvss":7.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","cvssSource":"cna","cwe":["CWE-416"],"vendor":"pavel-odintsov","product":"fastnetmon","affected":["fastnetmon <= 1.2.9"],"published":"2026-11-05","updated":"2026-11-05","sourceUpdated":"2026-11-05T22:31:58.734Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-93424","references":[{"url":"https://github.com/pavel-odintsov/fastnetmon/security/advisories/GHSA-ph88-95vc-x6gv","label":"https://github.com/pavel-odintsov/fastnetmon/security/advisories/GHSA-ph88-95vc-x6gv"},{"url":"https://github.com/pavel-odintsov/fastnetmon/commit/a24e528d145b5371a7ab0bcdde23e4b4b99506e9","label":"https://github.com/pavel-odintsov/fastnetmon/commit/a24e528d145b5371a7ab0bcdde23e4b4b99506e9"}],"tags":["cve.org"],"ingestedAt":"2026-11-05T23:41:31.943Z","epss":0.00278,"epssPercentile":0.20404,"slug":"CVE-2026-93424","body":"## Overview\n\nFastNetMon is a high-performance DDoS detector and sensor. In version 1.2.9 and earlier, peer_find_template() in src/netflow_plugin/netflow_collector.cpp and src/netflow_plugin/netflow_v9_collector.cpp returns a pointer into global_netflow9_templates after releasing the cache mutex. On deployments with at least two entries in netflow_ports, concurrent template redefinition and data-flowset processing can let add_update_peer_template() reassign the template and free its records vector while another listener dereferences the escaped pointer. An unauthenticated sender that can reach both NetFlow/IPFIX listener ports can trigger a heap-use-after-free and reliably crash FastNetMon. No fixed release is available as of this review.\n\n## Affected\n\n- `fastnetmon <= 1.2.9`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":41,"depthScoreParts":{"impact":41.3,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}