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TI-2026-85706 Aliases CVE-2026-93424

Use-after-free in FastNetMon NetFlow/IPFIX template cache

Priority LOW 33CWE-416Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-416 and the CVSS impact.

Summary

FastNetMon from pavel-odintsov is affected through version 1.2.9. The template cache lookup returns a pointer into the cache after releasing its mutex, so a concurrent template redefinition can free the memory while another listener still uses it (CWE-416). An unauthenticated remote attacker who can reach both NetFlow/IPFIX listener ports on a deployment with at least two netflow_ports entries can crash FastNetMon.

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

Description from the CNA

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_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.

Why it matters now

EPSS 0.00278 20th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
pavel-odintsovfastnetmonup to 1.2.9—No fix listedCNA
  • fastnetmon Vendorpavel-odintsov Affected up to 1.2.9 Fixed in — No fix listed CNA

Remediation

The sources list no fixed version for FastNetMon.

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-11-05 Threatist record created from CVE-2026-93424
  2. 2026-11-06 Affected versions changed · Red Hat
  3. 2026-11-06 CVSS score added · Red Hat
  4. 2026-11-07 Priority changed: MEDIUM → LOW

References

Other 2

  • TI-2026-85701 Out-of-bounds read in FastNetMon shared IPv6 packet parser CVSS 3.1HIGH 8.2
  • TI-2026-35974 FastNetMon Community Edition through 1.2.9 contains an off-by-one heap-based buffer… CVSS 3.1CRITICAL 9.8
  • TI-2026-35971 FastNetMon Community Edition through 1.2.9 contains a stack-based buffer overflow in the… CVSS 3.1CRITICAL 9.8
  • TI-2026-35976 FastNetMon Community Edition through 1.2.9 contains an integer overflow in the BGP… CVSS 3.1CRITICAL 9.8
  • TI-2026-35972 FastNetMon Community Edition through 1.2.9 contains an OS command injection vulnerability… CVSS 3.1CRITICAL 9.8
  • TI-2024-37109 An issue was discovered in FastNetMon Community Edition through 1.2.7. CVSS 3.1HIGH 7.5
See all 21 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences