What is the CVSS score of CVE-2026-48696?

CVE-2026-48696 has a CVSS 3.1 base score of 6.2 (Medium). CVSS vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. EPSS exploitation probability: 0.0%.

FastNetMon Community CVE-2026-48696

EUVD-2026-31950 MEDIUM

Classic Buffer Overflow (CWE-120)

2026-05-26 mitre

GHSA-vpc6-j22r-6mf9

Buffer Overflow N A

6.2

CVSS 3.1 · NVD

Severity by source

NVD PRIMARY

6.2 MEDIUM

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

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

Attack Vector

Local

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Lifecycle Timeline

Analysis Generated

May 27, 2026 - 19:41 vuln.today

CVSS changed

May 27, 2026 - 19:37 NVD

6.2 (MEDIUM)

CVE Published

May 26, 2026 - 00:00 nvd

UNKNOWN (no severity yet)

DescriptionNVD

FastNetMon Community Edition through 1.2.9 has a buffer overflow, a different vulnerability than CVE-2026-48686 and CVE-2026-48689.

AnalysisAI

Buffer overflow in FastNetMon Community Edition through 1.2.9 allows a local attacker with no privileges to crash the FastNetMon process, disabling DDoS detection and network monitoring capabilities. The vulnerability is specifically tied to a sprintf-based overflow in the ExaBGP integration component, as documented in the Lorikeetsecurity advisory. This is one of at least three distinct buffer overflow vulnerabilities (alongside CVE-2026-48686 and CVE-2026-48689) identified in the same product version, suggesting a broader audit surfaced a class of unsafe string-handling bugs. No public exploit identified at time of analysis, and the impact is limited to availability (denial of service) with no confidentiality or integrity exposure.

Technical ContextAI

FastNetMon is an open-source high-performance DDoS detection tool that monitors network traffic and can trigger mitigation actions via integrations including ExaBGP, a BGP route injector. The referenced blog post title ('exabgp-sprintf-overflow') identifies the vulnerable component as the ExaBGP integration layer, where a sprintf call performs unbounded string formatting into a fixed-size buffer - a textbook CWE-120 (Buffer Copy without Checking Size of Input) defect. On overflow, the write corrupts adjacent stack or heap memory, leading to a process crash. The CVSS vector AV:L/AC:L/PR:N/UI:N indicates the attack is locally triggered with no privilege requirement, consistent with an attacker who can influence ExaBGP messages or the inter-process communication channel between ExaBGP and FastNetMon on the host. The affected CPE entry is listed as 'n/a' in NVD, but the GitHub repository and version cap (through 1.2.9) are the authoritative scope indicators.

RemediationAI

No vendor-released patch version has been identified at time of analysis. The GitHub repository at https://github.com/pavel-odintsov/fastnetmon should be monitored for a patched release addressing CVE-2026-48696, CVE-2026-48686, and CVE-2026-48689 collectively. As a compensating control, restrict the ExaBGP inter-process communication channel to trusted local processes only using OS-level access controls (e.g., Unix socket permissions, SELinux/AppArmor policy), which addresses the PR:N/AV:L attack surface by limiting who can send input to the vulnerable code path. Additionally, consider running FastNetMon under a process supervisor (systemd with Restart=always) so that a crash-induced DoS results in automatic restart, reducing the window of DDoS detection blindness. Be aware that automatic restarts do not prevent repeated crash loops if an attacker has persistent local access. Detailed technical context for this CVE is available at https://lorikeetsecurity.com/blog/fastnetmon-cve-2026-48696-exabgp-sprintf-overflow.