Cyber Posture

CVE-2026-48690

High
Microsoft: not affectedMSmacOS: not affectedMacLinux: not affectedLnxMobile: not affectedMobNetwork: not affectedNetApplication: affectedAppOther: not affectedOth

Published: 26 May 2026

Published
26 May 2026
Modified
27 May 2026
KEV Added
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Patch
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CVSS Score 7.1 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
EPSS Score 0.0001 1.5th percentile
Risk Priority 14 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-48690 is a high-severity Heap-based Buffer Overflow (CWE-122) vulnerability in Pavel-Odintsov Fastnetmon. Its CVSS base score is 7.1 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 1.5th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

Threat & Defense at a Glance

What attackers do: exploitation maps to Exploit Public-Facing Application (T1190).
Threat & Defense Details

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
attack.mitre.org →
Why these techniques?

Integer overflow in packet capture buffer allocation enables remote heap corruption and code execution against the network monitoring service.

Confidence: HIGH · MITRE ATT&CK Enterprise v18.1

NVD Description

FastNetMon Community Edition through 1.2.9 contains an integer overflow vulnerability in the packet capture buffer allocation. In src/packet_storage.hpp, the allocate_buffer() function computes memory_size_in_bytes as 'buffer_size_in_packets * (max_captured_packet_size + sizeof(fastnetmon_pcap_pkthdr_t)) + sizeof(fastnetmon_pcap_file_header_t)' using unsigned int (32-bit) arithmetic. With max_captured_packet_size=1500 and sizeof(fastnetmon_pcap_pkthdr_t)=16,…

more

each packet requires approximately 1516 bytes. If buffer_size_in_packets exceeds approximately 2,832,542, the multiplication overflows, resulting in a much smaller allocation than expected. Subsequent write_packet() calls then write past the allocated buffer, causing heap corruption. The buffer_size_in_packets value is derived from the ban_details_records_count configuration parameter, which is parsed using atoi() with no overflow checking.

Deeper analysisAI

Automated synthesis unavailable for this CVE.

Details

CWE(s)
CWE-122CWE-190

Affected Products

pavel-odintsov
fastnetmon
≤ 1.2.9

EU & UK References

References