CVE-2026-85321

Status: Undergoing AnalysisHigh (7.5)—

Severity7.5High · CVSS 3.1

Exploitation probability1.06 %higher than 64% of CVEs

Active exploitationNonot in the CISA catalog

Public exploitNot knownno public code found

Allocation of resources without limits or throttling in Active Directory Federation Services (AD FS) allows an unauthorized attacker to deny service over a network.

CVSS

Base score: 7.5
Version: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 1.06 %
Percentile among all scored CVEs: 64
Score date: 10/21/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

ExploitationT1190 Exploit Public-Facing Applicationinitial access90 %
Primary impactT1499 Endpoint Denial of Serviceimpact90 %

Vector AV:N/PR:N/UI:N y CWE-770 en AD FS: asignación de recursos sin límites permite denegación de servicio remota sin autenticación (A:H).

Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.

ATT&CK mitigations that cover these techniques

Filter Network Traffic Vulnerability Scanning Privileged Account Management Network Segmentation Limit Access to Resource Over Network Application Isolation and Sandboxing

Affected technologies (1)

⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.

Microsoft — Active Directory Federation Services^AI

CWEs

CWE-770

References

Show 1 references

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-85321

Raw JSON (NVD)

Show

{
  "id": "CVE-2026-85321",
  "cveTags": [],
  "metrics": {
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      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-85321",
          "role": "CISA Coordinator",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "version": "2.0.3",
          "timestamp": "2026-10-13T20:15:28.381650Z"
        }
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    "cvssMetricV31": [
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          "baseSeverity": "HIGH",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
          "integrityImpact": "NONE",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "confidentialityImpact": "NONE"
        },
        "impactScore": 3.6,
        "exploitabilityScore": 3.9
      }
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  "published": "2026-10-13T19:20:53.400",
  "references": [
    {
      "url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-85321",
      "source": "secure@microsoft.com"
    }
  ],
  "vulnStatus": "Undergoing Analysis",
  "weaknesses": [
    {
      "type": "Secondary",
      "source": "secure@microsoft.com",
      "description": [
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          "value": "CWE-770"
        }
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    {
      "lang": "en",
      "value": "Allocation of resources without limits or throttling in Active Directory Federation Services (AD FS) allows an unauthorized attacker to deny service over a network."
    }
  ],
  "lastModified": "2026-10-13T21:19:12.130",
  "sourceIdentifier": "secure@microsoft.com"
}