Reference page — cumulative record through Wednesday, August 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.
n/a n/a — FastNetMon Community Edition through 1.2.9 contains an off-by-one heap-based buffer overflow in the dynamic_binary_buffer_t class (src/dy…
AV AC PR UI S C I A CVSS EPSS %ile KEV
N L N N U H H H 9.8 .0068 49.5 —
AFFECTED
Product Versions Fixed
n/a n/a – —
TIMELINE
May 22 Reserved by mitre
May 26 EXPLOIT PUBLISHED — CVE-2026-48689. Public exploit reference added.
May 26 Published (CNA: mitre)
Description
FastNetMon Community Edition through 1.2.9 contains an off-by-one heap-based buffer overflow in the dynamic_binary_buffer_t class (src/dynamic_binary_buffer.hpp). Five methods (append_dynamic_buffer, append_data_as_pointer, append_data_as_object_ptr, memcpy_from_ptr, memcpy_from_object_ptr) use an incorrect bounds check of the form 'if (offset + length > maximum_internal_storage_size + 1)' instead of the correct 'if (offset + length > maximum_internal_storage_size)'. This allows writing exactly one byte past the end of the heap-allocated buffer. The class is used pervasively in BGP message encoding/decoding, NetFlow template processing, and Flow Spec NLRI construction. An attacker who can send network traffic (NetFlow, sFlow, IPFIX, or BGP) to a FastNetMon instance can trigger this overflow, potentially achieving arbitrary code execution by corrupting heap metadata. Notably, the append_byte() method uses the correct bounds check, confirming the inconsistency.
Lifecycle
Complete event history — 3 events, chronological
| Date | Event | Detail |
|---|
| May 22, 2026 | Reserved | Reserved by mitre |
| May 26, 2026 | EXPLOIT PUBLISHED | EXPLOIT PUBLISHED — CVE-2026-48689. Public exploit reference added. |
| May 26, 2026 | Published | Published (CNA: mitre) |
Affected
Affected products and packages — 1 row
| Vendor | Product / Package | Ecosystem | Version introduced | Fixed |
|---|
| n/a | n/a | — | n/a | — |
About this page
This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-48689 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Wednesday, August 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.