Cisco IOS XE Software Local Privilege Escalation Vulnerability

published 2021-03-24 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-6857

cvss: 5.1; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 27%
public exploits: 0; none known

A vulnerability in one of the diagnostic test CLI commands of Cisco IOS XE Software could allow an authenticated, local attacker to execute arbitrary code on an affected device. To exploit this vulnerability, the attacker would need to have valid user credentials at privilege level 15. This vulnerability exists because the affected software permits modification of the run-time memory of an affected device under specific circumstances. An attacker could exploit this vulnerability by authenticating to the affected device and issuing a specific diagnostic test command at the CLI. A successful exploit could trigger a logic error in the code that was designed to restrict run-time memory modifications. The attacker could take advantage of this logic error to overwrite system memory locations and execute arbitrary code on the underlying Linux operating system (OS) of the affected device.

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 2 y ago (2024-11-08)

Exploit prediction

0.34% chance of exploitation in the next 30 days, higher than 27% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	5.1	CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:L/I:H/A:N
NVD	3.1	6.7	CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
NVD	2.0	7.2	AV:L/AC:L/Au:N/C:C/I:C/A:C

Affected products

Cisco Cisco IOS XE Software

Classification

Weakness

CWE-123 Write-what-where Condition

Technology feeds

Cisco IOS rss critical rss

References

tools.cisco.com /security/center/content/CiscoSecurityAdvisory/cisco-sa-XE-OFP-6Nezgn7b
vendor-advisory

Sources

CVE List CVE-2021-1390
NVD CVE-2021-1390

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Summary