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CVE-2019-17023

Status: ModifiedMedium (6.5)—

After a HelloRetryRequest has been sent, the client may negotiate a lower protocol that TLS 1.3, resulting in an invalid state transition in the TLS State Machine. If the client gets into this state, incoming Application Data records will be ignored. This vulnerability affects Firefox < 72.

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)

Canonical — Ubuntu LinuxDebian — Debian LinuxMozilla — Firefox

CWEs

References

Raw JSON (NVD)

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  "id": "CVE-2019-17023",
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          "vectorString": "AV:N/AC:M/Au:N/C:N/I:P/A:N",
          "authentication": "NONE",
          "integrityImpact": "PARTIAL",
          "accessComplexity": "MEDIUM",
          "availabilityImpact": "NONE",
          "confidentialityImpact": "NONE"
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          "value": "CWE-287"
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    }
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  "lastModified": "2026-06-17T02:23:10.707",
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