CVE-2026-48686
📛 CVE Title
CVE-2026-48686
Description
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_length directly from the BGP packet (line 99) without validating it is <= 32 for IPv4 prefixes. This value is passed to how_much_bytes_we_need_for_storing_certain_subnet_mask() which computes ceil(prefix_bit_length / 8), returning up to 32 bytes for a prefix_bit_length of 255. The result is used as the length argument to memcpy() (line 106), which copies into a 4-byte uint32_t stack variable (prefix_ipv4). This causes a stack buffer overflow of up to 28 bytes, which can be exploited for arbitrary code execution. Additionally, the unvalidated prefix_bit_length is passed to convert_cidr_to_binary_netmask_local_function_copy() (line 111), where a shift of (32 - cidr) with cidr > 32 causes undefined behavior.
Overview
- State
- PUBLISHED
- Assigner (CNA)
- mitre
- CVSS severity
- critical
- CVSS score
- 9.8 / 10
- CVSS vector
AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H- Effective score
- 9.8 / 10 CRITICAL source: CNA overview
- CWE(s)
- —
- Reserved
- 2026-05-22
- Published
- 2026-05-26 00:00 UTC
- Last updated
- 2026-05-26 20:59 UTC
- Source
- https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/48xxx/CVE-2026-48686.json
- Linked Threat
- CVE-2026-48686 — CVE-2026-48686
NVD triage scoring NVD CVE 2.0
Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.
- NVD published
- 2026-05-26 16:16:26 UTC
- NVD last modified
- 2026-07-24 11:10:00 UTC
- NVD CVSS v3.1
- 9.8 / 10 CRITICAL source: nvd@nist.gov
- NVD CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H- Exploitability subscore
- 3.9 / 10
- Impact subscore
- 5.9 / 10
- EPSS score
- 0.0056 (probability of exploitation in next 30 days)
- EPSS percentile
- 43.73% vs all CVEs — higher = more likely to be exploited, as of 2026-08-01
NVD-assigned CWE(s):
CWE-120,
CWE-787
(differs from the CNA list above)
NVD / KEV / EPSS data refreshed 2026-08-01 17:09 UTC. Re-run the 🛰 Backfill from NVD button above to refresh.
European Union Vulnerability Database ENISA EUVD
ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.
- EUVD ID
-
EUVD-2026-31842 - Assigner
- mitre
- Published
- May 26, 2026, 12:00:00 AM
- Updated
- May 26, 2026, 8:59:11 PM
- EUVD base score (CVSS 3.1)
-
9.8 / 10
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - EUVD-reported EPSS
- 0.5700
- Vendors
- n/a
- Products
-
n/a (n/a)
- Aliases
-
GHSA-7p7c-c3vp-p386
ENISA description: 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_length directly from the BGP packet (line 99) without validating it is <= 32 for IPv4 prefixes. This value is passed to how_much_bytes_we_need_for_storing_certain_subnet_mask() which computes ceil(prefix_bit_length / 8), returning up to 32 bytes for a prefix_bit_length of 255. The result is used as the length argument to memcpy() (line 106), which copies into a 4-byte uint32_t stack variable (prefix_ipv4). This causes a stack buffer overflow of up to 28 bytes, which can be exploited for arbitrary code execution. Additionally, the unvalidated prefix_bit_length is passed to convert_cidr_to_binary_netmask_local_function_copy() (line 111), where a shift of (32 - cidr) with cidr > 32 causes undefined behavior.
Affected products (1)
| Vendor | Product | Versions | Platforms |
|---|---|---|---|
| n/a | n/a |
n/a (affected)
|
— |
Affected products — CPE 2.3 (1) NVD
NVD's normalized CPE 2.3 matchers, used by vendor tools (vulnerability scanners, asset managers) for automated detection. Compare with the CNA's free-text "Affected products" section above.
cpe:2.3:a:pavel-odintsov:fastnetmon:*:*:*:*:community:*:*:*
Vendor references (3)
References embedded in the original CVE record by the assigning CNA.
Web references (6)
DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.
- https://github.com/pavel-odintsov/fastnetmon tenable:github.com
- https://github.com/pavel-odintsov/fastnetmon/blob/master/src/bgp_protocol.cpp tenable:github.com
- https://lorikeetsecurity.com/blog/fastnetmon-cve-2026-48686-bgp-nlri-stack-overflow tenable:lorikeetsecurity.com
- https://nvd.nist.gov/vuln/detail/CVE-2026-48686 tenable:nvd.nist.gov
- https://www.cve.org/CVERecord?id=CVE-2026-48686 tenable:www.cve.org
- https://www.first.org/epss/ tenable:www.first.org
NVD-tagged references (3)
Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.
- https://github.com/pavel-odintsov/fastnetmon cve@mitre.org Product
- https://github.com/pavel-odintsov/fastnetmon/blob/master/src/bgp_protocol.cpp cve@mitre.org Product
- https://lorikeetsecurity.com/blog/fastnetmon-cve-2026-48686-bgp-nlri-stack-overflow cve@mitre.org Third Party Advisory
Remediations (18)
Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.
-
web:blog.qualys.com
Oracle released its second quarterly edition of this year's Critical Patch Update. The update received patches for 481 security vulnerabilities.
2026-06-04 00:10 UTC -
web:blog.stefan-gossner.com
Important: If your current farm patch level is September 2025 CU, execute the following PowerShell script to correct the folder permissions on the relevant folders otherwise installing the SharePoint fixes will fail: Fix -SeptemberCU-Permission-Problem.ps1 Alternatively you can also remove the NT Authority\system account from WSS_WPG and IIS_IUSRS local security groups of the SharePoint ...
2026-06-04 00:10 UTC -
web:cybersecuritynews.com
Microsoft has released its April 2026 Patch Tuesday security update, addressing 168 vulnerabilities across its product portfolio including one actively exploited zero-day and one publicly disclosed flaw that organizations must prioritize immediately.
2026-06-04 00:10 UTC -
web:msrc.microsoft.com
The Microsoft Security Response Center (MSRC) investigates all reports of security vulnerabilities affecting Microsoft products and services, and provides the information here as part of the ongoing effort to help you manage security risks and help keep your systems protected.
2026-06-04 00:10 UTC -
web:nvd.nist.gov
An official website of the United States government Here's how you know
2026-06-04 00:10 UTC -
web:www.cisecurity.org
<p>Multiple vulnerabilities have been discovered in Microsoft products, the most severe of which could allow for remote code execution. Successful exploitation of the most severe of these vulnerabilities could result in an attacker gaining the same privileges as the logged-on user. Depending on the privileges associated with the user, an attacker could then install programs; view, change, or ...
2026-06-04 00:10 UTC -
web:www.crowdstrike.com
Microsoft's April 2026 Patch Tuesday addresses 164 CVEs , featuring 8 Critical vulnerabilities, one exploited zero-day, and one disclosed zero-day.
2026-06-04 00:10 UTC -
web:www.oracle.com
This Critical Security Patch Update contains 35 new security patches across the product families listed below. Please note that an MOS note summarizing the content of this Critical Security Patch Update and other Oracle Software Security Assurance activities is located at May 2026 Critical Security Patch Update: Executive Summary and Analysis.
2026-06-04 00:10 UTC -
web:www.windowslatest.com
Windows 11 April 2026 update adds Narrator Copilot support, faster Settings, File Explorer fixes, and key security improvements.
2026-06-04 00:10 UTC -
web:zecurit.com
Get the complete breakdown of Microsoft's June 2026 Patch Tuesday. We analyze the latest security updates and all critical CVEs .
2026-06-04 00:10 UTC -
web:blogs.oracle.com
For more information about the Critical Patch Update program, see the security vulnerability remediation practices page located on the Oracle Trust Center.
2026-06-19 02:26 UTC -
web:mondoo.com
CVE - 2026 -46868 - HIGH severity: Vulnerability in the Oracle Enterprise Manager Base Platform product of Oracle Enterprise Manager (component: Extensibility F...
2026-06-19 02:26 UTC -
web:oradba.ch
On April 21, 2026 , Oracle released the Critical Patch Update (CPU) for April 2026 — 481 new security fixes across the entire Oracle product stack. For Oracle Database, this means another round of mandatory patching. What makes this quarter unusual: several key Release Updates, including 19.31 and 23.26.2, were not available on release day and are delayed by up to a week or more.
2026-06-19 02:26 UTC -
web:portal.msrc.microsoft.com
The Security Update Guide provides information on the latest Microsoft security updates, helping users understand and address potential vulnerabilities effectively.
2026-06-19 02:26 UTC -
web:support.microsoft.com
This update for Windows 11, version 25H2 and 24H2 (KB5084597) incudes security improvements. To learn more about differences between security updates, optional non-security preview updates, out-of-band (OOB) updates, and continuous innovation, see Windows monthly updates explained. For information on Windows update terminology, see the different types of Windows software updates. To view the ...
2026-06-19 02:26 UTC -
web:www.oracle.com
This Critical Patch Update contains 481 new security patches across the product families listed below. Please note that an MOS note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at April 2026 Critical Patch Update: Executive Summary and Analysis.
2026-06-19 02:26 UTC -
web:www.tenable.com
Oracle addresses 241 CVEs in its April Critical Patch Update, the second quarterly update of 2026 with 481 patches, including 34 critical updates.
2026-06-19 02:26 UTC -
web:www.tenable.com
Vulnerability in the Oracle Enterprise Manager Base Platform product of Oracle Enterprise Manager (component: Extensibility Framework). Supported versions that are affected are 13.5 and 24.1. Easily exploitable vulnerability allows high privileged attacker with network access via HTTPS to compromise Oracle Enterprise Manager Base Platform. Successful attacks of this vulnerability can result in ...
2026-06-19 02:26 UTC
AI Forensic Analysis
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Raw JSON
The full cvelistV5 record. Download as CVE-2026-48686.json.
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