CVE-2026-48689

תיאור (מקור, אנגלית)

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.

מדדים

CVSS 3.1

9.8 (CRITICAL) מקור הציון: NVD CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS — סבירות ניצול

1% (אחוזון 000) נכון ל-5/8/2026

CWE

CWE-787, CWE-122, CWE-193

מוצרים מושפעים

pavel-odintsov: fastnetmon

קישורים

• https://lorikeetsecurity.com/blog/fastnetmon-cve-2026-48689-dynamic-buffer-off‮… ExploitThird Party Advisory
• https://github.com/pavel-odintsov/fastnetmon Product
• https://github.com/pavel-odintsov/fastnetmon/blob/master/src/dynamic_binary_bu‮… Product