CVE-2023-20135 - Vulnerability Details - OpenCVE

A vulnerability in Cisco IOS XR Software image verification checks could allow an authenticated, local attacker to execute arbitrary code on the underlying operating system. This vulnerability is due to a time-of-check, time-of-use (TOCTOU) race condition when an install query regarding an ISO image is performed during an install operation that uses an ISO image. An attacker could exploit this vulnerability by modifying an ISO image and then carrying out install requests in parallel. A successful exploit could allow the attacker to execute arbitrary code on an affected device.

No CVSS v4.0

Attack Vector Local

Attack Complexity High

Privileges Required High

Scope Unchanged

Confidentiality Impact High

Integrity Impact High

Availability Impact None

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

The EPSS score is 0.00016.

Exploitation none

Automatable no

Technical Impact total

Vendors	Products
Cisco	Ios Xr

Configuration 1 [-]

OR	cpe:2.3:o:cisco:ios_xr::::::::
	cpe:2.3:o:cisco:ios_xr::::::::

No data.

No data.

References

Link	Providers
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-lnt-L9zOkBz5

History

Tue, 16 Dec 2025 22:15:00 +0000

Type	Values Removed	Values Added
Metrics	ssvc `{'options': {'Automatable': 'No', 'Exploitation': 'None', 'Technical Impact': 'Total'}, 'version': '2.0.3'}`	ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}`

Wed, 23 Oct 2024 20:15:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'No', 'Exploitation': 'None', 'Technical Impact': 'Total'}, 'version': '2.0.3'}`

MITRE

Status: PUBLISHED

Assigner: cisco

Published: 2023-09-13T16:38:36.593Z

Updated: 2025-12-16T18:23:19.364Z

Reserved: 2022-10-27T18:47:50.351Z

Link: CVE-2023-20135

Vulnrichment

Updated: 2024-08-02T08:57:36.157Z

NVD

Status : Modified

Published: 2023-09-13T17:15:09.253

Modified: 2024-11-21T07:40:38.240

Link: CVE-2023-20135

Redhat

No data.

OpenCVE Enrichment

No data.

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