CVE-2021-34708 - CVE House
Back to Database
Status published Medium CVE-2021-34708

Cisco IOS XR Software for Cisco 8000 and Network Convergence System 540 Series Routers Image Verification Vulnerabilities

Vulnerability Description

Multiple vulnerabilities in image verification checks of Cisco Network Convergence System (NCS) 540 Series Routers, only when running Cisco IOS XR NCS540L software images, and Cisco IOS XR Software for Cisco 8000 Series Routers could allow an authenticated, local attacker to execute arbitrary code on the underlying operating system. For more information about these vulnerabilities, see the Details section of this advisory.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

THREAT MONITOR

Am I Vulnerable?

Launch our assessment wizard to check if your infrastructure is exposed to • CVE-2021-34708

Credits & Attribution

No credits recorded in the NVD database.

References

More from Cisco

View All →
CVE-2025-20393
Cisco Secure Email Gateway and Cisco Secure Email and Web Manager Remote Command Execution Vulnerability
Critical 10
CVE-2025-20377
Cisco Unified Intelligence Center API Information Disclosure Vulnerability
Medium 4.3
CVE-2025-20376
Cisco Unified Contact Center Express Remote Code Execution Vulnerability
Medium 6.5
CVE-2025-20375
Cisco Unified Contact Center Express Arbitrary File Upload Vulnerability
Medium 6.5
CVE-2025-20374
Cisco Unified Contact Center Express Arbitrary File Download Vulnerability
Medium 4.9

Affected Vendor

Affected Software

Cisco IOS XR Software
Vulnerable Versions:
Unknown

Timeline

Official Publish: September 9th, 2021
Last Modified: November 7th, 2024
Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N

Weaknesses (CWE)

CWE-347

MITRE ATT&CK TTPs

T1553 Subvert Trust Controls
Defense Evasion
T1190 Exploit Public-Facing Application
Initial Access
T1078 Valid Accounts
Persistence
T1550 Use Alternate Authentication Material
Defense Evasion
T1565 Data Manipulation
Impact