PT-2026-43310 · Unknown+2 · Fastnetmon Community Edition+2

CVE-2026-48691 · Published 2026-05-26 · Updated 2026-06-15

Positive Technologies (AI Summary)

CVSS v3.1

7.3

High

Base vector

AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L

Name of the Vulnerable Software and Affected Versions FastNetMon Community Edition versions prior to 1.2.10

Description An integer overflow exists in the BGP AS PATH attribute encoder. The IPv4UnicastAnnounce::get attributes() function calculates the attribute length and stores it in a uint8 t field. Because a uint8 t only supports values from 0 to 255, an AS PATH containing more than 63 ASNs causes silent truncation. This truncated length is used for buffer sizing, but the full untruncated data is written, leading to a heap buffer overflow. Additionally, the path segment length field is also a uint8 t, which results in truncation when more than 255 ASNs are present.

Recommendations Update to version 1.2.10 or later.

Exploit

Fix

Heap Based Buffer Overflow

Integer Overflow

Weakness Enumeration

CWE-122

CWE-190

Related Identifiers

CVE-2026-48691

USN-8429-1

Affected Products

Fastnetmon Community Edition

Linuxmint

Ubuntu

References · 21

• 🔥 https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/48xxx/CVE-2026-48691.json · Exploit
• https://cve.org/CVERecord?id=CVE-2026-48691 · Security Note
• https://ubuntu.com/security/CVE-2026-48687 · Vendor Advisory
• https://ubuntu.com/security/CVE-2026-48689 · Vendor Advisory
• https://osv.dev/vulnerability/UBUNTU-CVE-2026-48691 · Vendor Advisory
• https://osv.dev/vulnerability/CVE-2026-48691 · Vendor Advisory
• https://osv.dev/vulnerability/USN-8429-1 · Vendor Advisory
• https://ubuntu.com/security/CVE-2026-48694 · Vendor Advisory
• https://ubuntu.com/security/CVE-2026-48686 · Vendor Advisory
• https://ubuntu.com/security/CVE-2026-48691 · Vendor Advisory
• https://ubuntu.com/security/notices/USN-8429-1 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-48691 · Security Note
• https://osv.dev/vulnerability/DEBIAN-CVE-2026-48691 · Vendor Advisory
• https://security-tracker.debian.org/tracker/CVE-2026-48691 · Vendor Advisory
• https://github.com/pavel-odintsov/fastnetmon · Note