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TI-2026-85701 Aliases CVE-2026-92693

Out-of-bounds read in FastNetMon shared IPv6 packet parser

Priority HIGH 75CWE-125Published · Updated

Key facts

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

Attack profile from CVSS 3.1 · CNA. Fix status from CNA.

Summary

FastNetMon through 1.2.9 contains an out-of-bounds read in its shared packet parser, parse_raw_packet_to_simple_packet_full(). The parser reads an IPv6 Fragment header without first checking that all eight bytes are present (CWE-125). An unauthenticated remote attacker can reach this parser with a crafted sFlow v5 RAW_PACKET_HEADER record that omits the Fragment bytes. The advisory does not establish a production process crash.

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, parse_raw_packet_to_simple_packet_full() in src/simple_packet_parser_ng.cpp dereferences ipv6_extension_header_fragment_t when IpProtocolNumberIPV6_FRAG is present without first verifying that the eight-byte Fragment header remains. A crafted sFlow v5 RAW_PACKET_HEADER record can remotely reach this shared parser with the Fragment bytes omitted, causing an unauthenticated remote out-of-bounds read. The supplied harness detects the read under AddressSanitizer, but the advisory does not establish a production process crash. No fixed release is available as of this review.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00258 17th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

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-2026-92693
  2. 2026-11-06 Affected versions changed · Red Hat
  3. 2026-11-06 CVSS score added · Red Hat
  4. 2026-11-06 CISA SSVC decision points changed
  5. 2026-11-06 Priority changed: MEDIUM → HIGH

References

Other 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
  • TI-2024-37108 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