Vulnerability-Lookup

CVE-2026-20321 (GCVE-0-2026-20321)

Vulnerability from cvelistv5 – Published: 2026-10-07 16:11 – Updated: 2026-10-08 15:33

Title

Cisco Application Policy Infrastructure Controller API Command Injection Vulnerability

Summary

A vulnerability in the web-based management API for Cisco Application Policy Infrastructure Controller (APIC) could allow an authenticated, remote attacker to execute arbitrary commands as the root user. To exploit this vulnerability, the attacker must have valid administrative credentials. This vulnerability is due to insufficient input validation of user-controlled command arguments. An attacker could exploit this vulnerability by authenticating using the API and sending crafted input. A successful exploit could allow the attacker to execute arbitrary commands on the underlying operating system of an affected device with root-level privileges.

Severity

6.5 (Medium)


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

SSVC

Exploitation: none Automatable: no Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-10-08 15:33 UTC

CWE

CWE-544 - Missing Standardized Error Handling Mechanism

Assigner

cisco CNA under the mitre root

CNA scorecard C 66/100 over 395 records in the last 180 days details

References

1 reference

URL	Tags
https://sec.cloudapps.cisco.com/security/center/c…

Impacted products

1 product

Vendor	Product	Version	CPE status
Cisco	Cisco Application Policy Infrastructure Controller (APIC)	Affected: 5.3(1d) Affected: 5.3(2a) Affected: 5.3(2b) Affected: 5.3(2c) Affected: 5.3(2d) Affected: 5.3(2e) Affected: 5.3(2f) Affected: 6.1(5e) Affected: 6.2(1f) Affected: 6.2(1g) Affected: 6.2(2e)	guessed

Show details on NVD website

JSON

To clipboard

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CISCO-SA-APIC-CMDINJ-L6VR4E7

Vulnerability from csaf_cisco - Published: 2026-10-07 16:00 - Updated: 2026-10-07 16:00

Summary

Cisco Application Policy Infrastructure Controller API Command Injection Vulnerability

Scope

1 vulnerability in this advisory, including CVE-2026-20321.

CVE-2026-20321

6.5 (Medium)


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

Known affected: 11 products

https://software.cisco.com

Open the full advisory

FKIE_CVE-2026-20321

Vulnerability from fkie_nvd - Published: 2026-10-07 17:16 - Updated: 2026-10-08 20:08

Severity

6.5 (Medium) - CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N

Summary

References

	URL	Tags
	psirt@cisco.com	https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-apic-cmdinj-L6VR4E7

Impacted products

	Vendor	Product	Version

JSON

To clipboard

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          "defaultStatus": "unknown",
          "product": "Cisco Application Policy Infrastructure Controller (APIC)",
          "vendor": "Cisco",
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            {
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              "version": "5.3(2f)"
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              "version": "6.1(5e)"
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            {
              "status": "affected",
              "version": "6.2(1f)"
            },
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              "status": "affected",
              "version": "6.2(1g)"
            },
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    }
  ],
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  "lastModified": "2026-10-08T20:08:45.857",
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}

GHSA-R72R-FHV8-5QGQ

Vulnerability from github – Published: 2026-10-07 18:32 – Updated: 2026-10-07 18:32

Details

This vulnerability is due to insufficient input validation of user-controlled command arguments. An attacker could exploit this vulnerability by authenticating using the API and sending crafted input. A successful exploit could allow the attacker to execute arbitrary commands on the underlying operating system of an affected device with root-level privileges.

Severity

6.5 (Medium)


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

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2026-20321"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-544"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-10-07T17:16:55Z",
    "severity": "MODERATE"
  },
  "details": "A vulnerability in the web-based management API for Cisco Application Policy Infrastructure Controller (APIC) could allow an authenticated, remote attacker to execute arbitrary commands as the root user. To exploit this vulnerability, the attacker must have valid administrative credentials.\n\nThis vulnerability is due to insufficient input validation of user-controlled command arguments. An attacker could exploit this vulnerability by authenticating using the API and sending crafted input. A successful exploit could allow the attacker to execute arbitrary commands on the underlying operating system of an affected device with root-level privileges.",
  "id": "GHSA-r72r-fhv8-5qgq",
  "modified": "2026-10-07T18:32:10Z",
  "published": "2026-10-07T18:32:10Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-20321"
    },
    {
      "type": "WEB",
      "url": "https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-apic-cmdinj-L6VR4E7"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N",
      "type": "CVSS_V3"
    }
  ]
}

NCSC-2026-0409

Vulnerability from csaf_ncscnl - Published: 2026-10-09 07:12 - Updated: 2026-10-09 07:12

Summary

Kwetsbaarheden verholpen in Cisco APIC

Scope

5 vulnerabilities in this advisory, including CVE-2026-20321.

CVE-2026-20321

A vulnerability in Cisco APIC's web-based management API allows an authenticated attacker with administrative credentials to execute arbitrary root-level commands due to insufficient input validation.

6.5 (Medium)


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

Known affected: 1 product

Open the full advisory

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

Action not permitted

CVE-2026-20321 (GCVE-0-2026-20321)

CISCO-SA-APIC-CMDINJ-L6VR4E7

FKIE_CVE-2026-20321

GHSA-R72R-FHV8-5QGQ

NCSC-2026-0409

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Nomenclature

Related by attack behaviour