CVE-2021-1388
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 o...
Affects 2 products across 1 vendor.
Software does not properly assign, modify, track, or check privileges, allowing unauthorized elevation of access.
Mapping is CWE-to-CAPEC per MITRE CAPEC 3.9.
A critical vulnerability in the API endpoint of Cisco ACI Multi-Site Orchestrator (MSO) allows unauthenticated remote attackers to bypass authentication due to improper token validation.
BSID: BS-2021-GLOBAL-081288-C • Model: /workspace/models/qwen2.5-coder-32b-instruct-bf16 • Confidence: HIGH
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What systems are affected by CVE-2021-1388?
| CVE ID | CVE-2021-1388 |
|---|---|
| BSID | BS-2021-GLOBAL-081288-C BreachSpider Global ID |
| CVSS Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H |
| Published | 2021-02-24 |
| Last Modified | 2026-06-17 |
| ICS Relevance | 70% |
| Weakness (CWE) | |
| Domains | |
| Source | NVD |
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.
Source: NIST NVD / MITRE CVE Database
An attacker can exploit this vulnerability by sending a crafted request to the affected API endpoint, potentially gaining unauthorized access to the system.
Exploitation Likelihood: CRITICAL
| Vendor | Product | Affected Versions |
|---|---|---|
| Cisco | Application Policy Infrastructure Controller | 3.0(3i) |
| Cisco | Aci Multi-Site Orchestrator | ≥ 3.0, < 3.0(3m) |
| CISA known-exploited | Not in KEV catalog |
|---|---|
| Public Exploit | Not confirmed |
| PoC Code | Not confirmed |
AI Enrichment Record — provenance & audit hash
| Model | /workspace/models/qwen2.5-coder-32b-instruct-bf16 |
|---|---|
| Confidence | HIGH |
| Enriched At | 2026-05-24 |
| SHA-512 Audit Hash | 05cbea37b9fe6ab9e47796b39811eb9fd1019bab45761ddef9a6bba65af9cff67d9fd7936fdfca1e8f9759dd283e8becc9b550a30aabf1aec67ea923792f8d6d |
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