Is CVE-2012-4099 being actively exploited?

CVE-2012-4099 is not currently listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

What is the CVSS score for CVE-2012-4099?

CVE-2012-4099 has a CVSS 2.0 base score of 4.3 (MEDIUM).

CVE-2012-4099

MEDIUM · CVSS 4.3EPSS 1.6%EU EUVD

The BGP implementation in Cisco NX-OS does not properly filter AS paths, which allows remote attackers to cause a denial of service (BGP service reset and resync) via a malformed UPDATE message, aka Bug ID CSCtn13065.

Key facts

CVSS score: 4.3 (v2.0)
Severity: MEDIUM
CVSS vector: AV:N/AC:M/Au:N/C:N/I:N/A:P
Weakness (CWE): CWE-20
EPSS score: 1.6% (76th percentile)
In CISA KEV: No
In EU EUVD: Yes (EUVD-2012-4043)
Published: October 14, 2013
NVD last modified: June 16, 2026
Status: Modified

EU Vulnerability Database (EUVD)

This vulnerability is also tracked by ENISA as EUVD-2012-4043 in the EU Vulnerability Database. Last updated in EUVD on September 17, 2024.

View on the EU Vulnerability Database

Affected products

cisco / nx-os

References

http://osvdb.org/98130
http://tools.cisco.com/security/center/content/CiscoSecurityNotice/CVE-2012-4099(Vendor Advisory)

Last updated September 17, 2026 · Source: NVD, CISA KEV, FIRST.org EPSS

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