What is CVE-2026-48686?

CVE-2026-48686 is a critical-severity vulnerability in Pavel-odintsov Fastnetmon, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 9.8/10. Published 2026-05-26.

How severe is CVE-2026-48686?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Buffer overflow in Pavel-odintsov Fastnetmon

CVE-2026-48686

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…

Vulnerability class: Buffer Overflow

EPSS: 0.000 (9.9th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Pavel-odintsov Fastnetmon
N/a — versions n/a

Weakness classification (CWE)

References

cve@mitre.org (Product)
cve@mitre.org (Product)
cve@mitre.org (Third Party Advisory)

Frequently asked questions

What is CVE-2026-48686?: CVE-2026-48686 is a critical-severity vulnerability in Pavel-odintsov Fastnetmon, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 9.8/10. Published 2026-05-26.
How severe is CVE-2026-48686?: Critical severity. CVSS v3 base score is 9.8 out of 10.