CVE intelligence and bounded remediation

CVE-2026-48688 — FastNetMon Community Edition through 1.2.9 contains multiple out-of-bounds reads in the BGP MP_REACH_NLRI IPv6 attribute decoder

High CVSS 7.5

FastNetMon Community Edition through 1.2.9 contains multiple out-of-bounds reads in the BGP MP_REACH_NLRI IPv6 attribute decoder. The function decode_mp_reach_ipv6() in src/bgp_protocol.cpp contains a TODO comment at line 156 explicitly acknowledging 'we should add sanity checks to avoid reads after attribute memory block.' The function casts raw pointers to structure types without verifying sufficient data exists (line 158), uses the attacker-controlled length_of_next_hop field to determine memcpy size (line 181), and computes prefix_length by dereferencing a pointer calculated from multiple attacker-controlled offsets without bounds validation (line 189). The prefix_length is then used to calculate number_of_bytes_required_for_prefix which becomes a memcpy length (line 202) with no check against remaining buffer size.

Severity
High
CVSS
7.5 (3.1)
Published
2026-05-26
CISA KEV
Not currently listed
Ecosystem
software/application
Weaknesses
CWE-125

Affected products

  • pavel-odintsov / fastnetmon

Matched remediation archetype

Buffer bounds, memory safety, and memory corruption

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Identify affected native-code versions, build flags, architectures, parsers, codecs, drivers, and input paths in all shipped artifacts.
  • Determine whether untrusted data reaches the affected routine and the process privilege, sandbox, and network exposure.
  • Confirm statically linked, vendored, firmware, and platform-provided copies, not only package-manager records.

Remediate safely

  • Apply the maintained upstream correction or replace the affected component, then rebuild every dependent artifact from clean inputs.
  • Adopt bounds-checked interfaces, validated sizes and integer conversions, clear ownership, and memory-safe components where practical.
  • Enable supported compiler and runtime hardening and add sanitized tests and fuzz regression seeds derived from non-weaponized fixtures.

Authoritative sources

Complete CVE record and remediation plan

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