CVE-2021-1256

Low

No strong exploitation signal.

CVSS base

6.0 MEDIUM

CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:H

EPSS — probability of exploitation (30 days)

0.5%

41.6th percentile

CISA KEV

Not listed

Weakness / dates

CWE-22

Published 2021-04-29 · modified 2026-08-11

CVSS breakdown

CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:H

Attack Vector	L	Local
Attack Complexity	L	Low
Privileges Required	H	High
User Interaction	N	None
Scope	U	Unchanged
Confidentiality	N	None
Integrity	H	High
Availability	H	High

Timeline

2021-04-29 — Published (NVD)
2026-08-11 — Last modified (NVD)

Description

A vulnerability in the CLI of Cisco Firepower Threat Defense (FTD) Software could allow an authenticated, local attacker to overwrite files on the file system of an affected device by using directory traversal techniques. A successful exploit could cause system instability if important system files are overwritten. This vulnerability is due to insufficient validation of user input for the file path in a specific CLI command. An attacker could exploit this vulnerability by logging in to a targeted device and issuing a specific CLI command with crafted user input. A successful exploit could allow the attacker to overwrite arbitrary files on the file system of the affected device. The attacker would need valid user credentials on the device.

Affected

cisco

References

Official: NVD · CVE.org