CVE-2021-34753
Low
No strong exploitation signal.
CVSS base
5.8
MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N
EPSS — probability of exploitation (30 days)
0.7%
50.2th percentile
CISA KEV
Not listed
Weakness / dates
CWE-284
Published 2024-11-15 · modified 2026-08-11
CVSS breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N
| Attack Vector | N | Network |
| Attack Complexity | L | Low |
| Privileges Required | N | None |
| User Interaction | N | None |
| Scope | C | Changed |
| Confidentiality | N | None |
| Integrity | L | Low |
| Availability | N | None |
Timeline
- 2024-11-15 — Published (NVD)
- 2026-08-11 — Last modified (NVD)
Description
A vulnerability in the payload inspection for Ethernet Industrial Protocol (ENIP) traffic for Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to bypass configured rules for ENIP traffic. This vulnerability is due to incomplete processing during deep packet inspection for ENIP packets. An attacker could exploit this vulnerability by sending a crafted ENIP packet to the targeted interface. A successful exploit could allow the attacker to bypass configured access control and intrusion policies that should trigger and drop for the ENIP packet.