cve-2020-2035
Vulnerability from cvelistv5
Published
2020-08-12 00:00
Modified
2024-08-04 06:54
Severity
Summary
PAN-OS: URL filtering policy is not enforced on TLS handshakes for decrypted HTTPS sessions
Impacted products
VendorProduct
Palo Alto NetworksPAN-OS
Show details on NVD website


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      "title": "PAN-OS: URL filtering policy is not enforced on TLS handshakes for decrypted HTTPS sessions",
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          "value": "Customers concerned about the risk described in this advisory are encouraged to review the KB article https://knowledgebase.paloaltonetworks.com/KCSArticleDetail?id=kA14u0000008V4J for more information on background and mitigation options. To enforce URL filtering policy on TLS handshakes for decrypted HTTPS sessions, we suggest you use any one of the following workarounds:\n\n1. Route outbound traffic between two virtual systems (vsys) on PAN-OS firewalls that have vsys capability and perform URL Filtering on one vsys and perform SSL/TLS Decryption on the other vsys.\n\n2. Add two additional Security Zones and route outbound traffic between the two zones so that you can apply both \"Decrypt\" and \"No Decrypt\" Decryption policy rules. For example, configure your next-generation firewall so that traffic travels from the Inside zone to the Internal-DMZ zone where you applied a \u201cNo Decrypt\u201d rule along with URL Filtering and then the traffic passes to the External-DMZ zone and from External-DMZ to the Internet zone where you applied a \"Decrypt\" rule. Be aware that this workaround configuration may significantly increase the load on your firewall.\n\n3. Use the additional security device in the traffic chain. \nThe SSL/TLS Decryption and URL Filtering functions should be separated (for example, the first device is performing URL Filtering and the second device is performing SSL/TLS Decryption).\n\nThese workarounds are described in detail at https://knowledgebase.paloaltonetworks.com/KCSArticleDetail?id=kA14u0000008V4J\n\nWe recommend you use an endpoint protection solution such as the Cortex XDR agent to significantly reduce the potential risk of hosts being compromised. See https://www.paloaltonetworks.com/cortex/endpoint-protection.\n\nCaution: We recommend that you do not disable SSL/TLS Decryption as a workaround to this issue. There are additional risks associated with this action. \n"
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    "cveId": "CVE-2020-2035",
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    "dateReserved": "2019-12-04T00:00:00",
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No afecta a la confidencialidad ni a la disponibilidad de un cortafuegos. Se considera que tiene un impacto bajo en la integridad del cortafuegos porque \u00e9ste no aplica una pol\u00edtica sobre cierto tr\u00e1fico que deber\u00eda haber sido bloqueado. Este problema no afecta a la aplicaci\u00f3n de la pol\u00edtica de filtrado de URL en las transacciones web de texto claro o cifrado. Esta t\u00e9cnica s\u00f3lo puede utilizarse despu\u00e9s de que un actor malicioso haya comprometido un host en la red protegida y la funci\u00f3n de descifrado TLS/SSL est\u00e9 habilitada para el tr\u00e1fico que el atacante controla. Palo Alto Networks no tiene conocimiento de ning\u00fan malware que utilice esta t\u00e9cnica para exfiltrar datos. Este problema es aplicable a todas las versiones actuales de PAN-OS. 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  }
}


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