TI-2021-00855 Aliases CVE-2021-1128 GHSA-rcpm-5qw3-5cwf

Cisco IOS XR Software Unauthorized Information Disclosure Vulnerability

LOW 25CWE-201Published 2021-02-04 · Updated 2024-11-08

Key facts

Attack vector: Local
Privileges required: Low
User interaction: None
Attack complexity: Low
Impact type: Information disclosure
Confidentiality · integrity · availability: High · None · None
Fix status: No fix listed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-201.

Summary

A vulnerability in the CLI parser of Cisco IOS XR Software could allow an authenticated, local attacker to view more information than their privileges allow. The vulnerability is due to insufficient application of restrictions during the execution of a specific command. An attacker could exploit this vulnerability by using a specific command at the command line. A successful exploit could allow the attacker to obtain sensitive information within the configuration that otherwise might not have been accessible beyond the privileges of the invoking user.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.00358 29th percentileScored 2026-11-07

Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: No
Technical impact: Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
Cisco	Cisco IOS XR Software	all versions	—	No fix listed	CNA

Cisco IOS XR Software VendorCisco Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 3

CPE	Versions	Role	Vendor
cpe:2.3:o:cisco:ios_xr::::::::	before 7.1.2	Vulnerable	Cisco
cpe:2.3:o:cisco:ios_xr:7.2.0:::::::*	7.2.0	Vulnerable	Cisco
cpe:2.3:o:cisco:ios_xr:7.3.0:::::::*	7.3.0	Vulnerable	Cisco

cpe:2.3:o:cisco:ios_xr:*:*:*:*:*:*:*:* Versions before 7.1.2 Vulnerable ·Cisco
cpe:2.3:o:cisco:ios_xr:7.2.0:*:*:*:*:*:*:* Versions 7.2.0 Vulnerable ·Cisco
cpe:2.3:o:cisco:ios_xr:7.3.0:*:*:*:*:*:*:* Versions 7.3.0 Vulnerable ·Cisco

Remediation

No fixed version listed by the sources yet.

Timeline

2026-10-02 Threatist record created from CVE-2021-1128
2026-10-03 Alias added: GHSA-rcpm-5qw3-5cwf

References

Advisory 1

20210203 Cisco IOS XR Software Unauthorized Information Disclosure Vulnerability

TI-2020-02680 Cisco IOS XR Software Cisco Discovery Protocol Format String Vulnerability KEVCVSS 3.1HIGH 8.8
TI-2018-00135 Memory corruption in Cisco IOS, IOS XE, and IOS XR KEVCVSS 3.1HIGH 8.8
TI-2020-03113 Cisco IOS XR Software DVMRP Memory Exhaustion Vulnerabilities KEVCVSS 3.1HIGH 8.6
TI-2020-03110 Cisco IOS XR Software DVMRP Memory Exhaustion Vulnerability KEVCVSS 3.1HIGH 8.6
TI-2018-00142 Memory corruption in Cisco IOS, IOS XE, and IOS XR KEVCVSS 3.1HIGH 8.0
TI-2023-23979 The HTTP/2 protocol allows a denial of service (server resource consumption) because… KEVCVSS 3.1HIGH 7.5

See all 199 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences