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CVE-2021-32919

Status: ModifiedHigh (7.5)—

An issue was discovered in Prosody before 0.11.9. The undocumented dialback_without_dialback option in mod_dialback enables an experimental feature for server-to-server authentication. It does not correctly authenticate remote server certificates, allowing a remote server to impersonate another server (when this option is enabled).

CVSS

Exploitation probability (EPSS)

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).

Affected technologies (3)

Debian — Debian LinuxFedoraproject — FedoraProsody — Prosody

CWEs

References

Raw JSON (NVD)

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{
  "id": "CVE-2021-32919",
  "cveTags": [],
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          "vectorString": "AV:N/AC:M/Au:N/C:P/I:N/A:N",
          "authentication": "NONE",
          "integrityImpact": "NONE",
          "accessComplexity": "MEDIUM",
          "availabilityImpact": "NONE",
          "confidentialityImpact": "PARTIAL"
        },
        "acInsufInfo": false,
        "impactScore": 2.9,
        "baseSeverity": "MEDIUM",
        "obtainAllPrivilege": false,
        "exploitabilityScore": 8.6,
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      "lang": "en",
      "value": "An issue was discovered in Prosody before 0.11.9. The undocumented dialback_without_dialback option in mod_dialback enables an experimental feature for server-to-server authentication. It does not correctly authenticate remote server certificates, allowing a remote server to impersonate another server (when this option is enabled)."
    },
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      "value": "Se detectó un problema en Prosody versiones anteriores a 0.11.9. La opción no documentada dialback_without_dialback en la función mod_dialback habilita una funcionalidad experimental para la autenticación de servidor a servidor. No autentica correctamente los certificados de servidor remoto, permitiendo que un servidor remoto suplante a otro servidor (cuando esta opción está habilitada)"
    }
  ],
  "lastModified": "2026-06-17T03:53:47.970",
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}