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CVE-2019-1691

Status: ModifiedMedium (5.8)—

A vulnerability in the detection engine of Cisco Firepower Threat Defense Software could allow an unauthenticated, remote attacker to cause the unexpected restart of the SNORT detection engine, resulting in a denial of service (DoS) condition. The vulnerability is due to the incomplete error handling of the SSL or TLS packet header during the connection establishment. An attacker could exploit this vulnerability by sending a crafted SSL or TLS packet during the connection handshake. An exploit could allow the attacker to cause the SNORT detection engine to unexpectedly restart, resulting in a partial DoS condition while the detection engine restarts. Versions prior to 6.2.3.4 are affected.

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 (1)

Cisco — Secure Firewall Threat Defense

CWEs

References

Raw JSON (NVD)

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  "id": "CVE-2019-1691",
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  "published": "2019-02-21T20:29:00.417",
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  "lastModified": "2026-08-11T19:37:30.880",
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