Improper input validation in Cisco iOS

CVE-2014-2109

The TCP Input module in Cisco IOS 12.2 through 12.4 and 15.0 through 15.4, when NAT is used, allows remote attackers to cause a denial of service (memory consumption or device reload) via crafted TCP packets, aka Bug IDs CSCuh33843 and CSCuj41494.

Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)

Published 2014-03-27 · last modified 2026-06-17.

CVSS v2 metric

CVSS v2 base score 7.8 (High). Vector: AV:N/AC:L/Au:N/C:N/I:N/A:C. This CVE predates CVSS v3 and has no v3 score from NVD.

EPSS exploit prediction

EPSS: 0.022 (82.1th percentile), scored 2026-09-30.

Low probability of exploitation in the next 30 days, but still tracked. 82nd percentile — 82.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.022 · newest: 0.022 · change: 0.000

Affected products

Cisco iOS — versions 12.2, 12.3, 12.4

Weakness classification (CWE)

CWE-20 — Improper Input Validation

References

tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20140326… (vendor-advisory, Vendor Advisory)
www.securityfocus.com/bid/66470 (vdb-entry)