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TI-2026-35971 Aliases CVE-2026-48686GHSA-7p7c-c3vp-p386

FastNetMon Community Edition through 1.2.9 contains a stack-based buffer overflow in the…

Priority MEDIUM 50CWE-120Published · Updated

Key facts

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

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA. Impact type from CWE-120 and the CVSS impact.

Summary

FastNetMon Community Edition through 1.2.9 contains a stack-based buffer overflow in the BGP NLRI (Network Layer Reachability Information) decoder. The function decode_bgp_subnet_encoding_ipv4_raw() in src/bgp_protocol.cpp reads prefix_bit_length directly from the BGP packet (line 99) without validating it is <= 32 for IPv4 prefixes. This value is passed to how_much_bytes_we_need_for_storing_certain_subnet_mask() which computes ceil(prefix_bit_length / 8), returning up to 32 bytes for a prefix_bit_length of 255. The result is used as the length argument to memcpy() (line 106), which copies into a 4-byte uint32_t stack variable (prefix_ipv4). This causes a stack buffer overflow of up to 28 bytes, which can be exploited for arbitrary code execution. Additionally, the unvalidated prefix_bit_length is passed to convert_cidr_to_binary_netmask_local_function_copy() (line 111), where a shift of (32 - cidr) with cidr > 32 causes undefined behavior.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00565 47th 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
None
Automatable
Yes
Technical impact
Total

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

Affected products

VendorProductAffected versionsFixed inStatusSource
——all versions—No fix listedCNA
  • — Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:pavel-odintsov:fastnetmon:*:*:*:*:community:*:*:*up to 1.2.9Vulnerablepavel-odintsov
  • cpe:2.3:a:pavel-odintsov:fastnetmon:*:*:*:*:community:*:*:* Versions up to 1.2.9 Vulnerable ·pavel-odintsov

Remediation

No fixed version listed by the sources yet.

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-48686
  2. 2026-10-03 Alias added: GHSA-7p7c-c3vp-p386
  3. 2026-10-25 EPSS moved to the below the 50th percentile

References

Advisory 1

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-2026-35976 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
  • TI-2026-35980 FastNetMon Community Edition through 1.2.9 contains an OS command injection vulnerability… CVSS 3.1HIGH 8.1
See all 15 →

Sources

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