github - ghsa-j3cp-2wgv-xj2j

ghsa-j3cp-2wgv-xj2j

Vulnerability from github

Published

2022-05-24 17:25

Modified

2022-05-24 17:25

Details

When SSL/TLS Forward Proxy Decryption mode has been configured to decrypt the web transactions, the PAN-OS URL filtering feature inspects the HTTP Host and URL path headers for policy enforcement on the decrypted HTTPS web transactions but does not consider Server Name Indication (SNI) field within the TLS Client Hello handshake. This allows a compromised host in a protected network to evade any security policy that uses URL filtering on a firewall configured with SSL Decryption in the Forward Proxy mode. A malicious actor can then use this technique to evade detection of communication on the TLS handshake phase between a compromised host and a remote malicious server. This technique does not increase the risk of a host being compromised in the network. It does not impact the confidentiality or availability of a firewall. This is considered to have a low impact on the integrity of the firewall because the firewall fails to enforce a policy on certain traffic that should have been blocked. This issue does not impact the URL filtering policy enforcement on clear text or encrypted web transactions. This technique can be used only after a malicious actor has compromised a host in the protected network and the TLS/SSL Decryption feature is enabled for the traffic that the attacker controls. Palo Alto Networks is not aware of any malware that uses this technique to exfiltrate data. This issue is applicable to all current versions of PAN-OS.

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{
  "affected": [],
  "aliases": [
    "CVE-2020-2035"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-20"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2020-08-12T17:15:00Z",
    "severity": "LOW"
  },
  "details": "When SSL/TLS Forward Proxy Decryption mode has been configured to decrypt the web transactions, the PAN-OS URL filtering feature inspects the HTTP Host and URL path headers for policy enforcement on the decrypted HTTPS web transactions but does not consider Server Name Indication (SNI) field within the TLS Client Hello handshake. This allows a compromised host in a protected network to evade any security policy that uses URL filtering on a firewall configured with SSL Decryption in the Forward Proxy mode. A malicious actor can then use this technique to evade detection of communication on the TLS handshake phase between a compromised host and a remote malicious server. This technique does not increase the risk of a host being compromised in the network. It does not impact the confidentiality or availability of a firewall. This is considered to have a low impact on the integrity of the firewall because the firewall fails to enforce a policy on certain traffic that should have been blocked. This issue does not impact the URL filtering policy enforcement on clear text or encrypted web transactions. This technique can be used only after a malicious actor has compromised a host in the protected network and the TLS/SSL Decryption feature is enabled for the traffic that the attacker controls. Palo Alto Networks is not aware of any malware that uses this technique to exfiltrate data. This issue is applicable to all current versions of PAN-OS.",
  "id": "GHSA-j3cp-2wgv-xj2j",
  "modified": "2022-05-24T17:25:24Z",
  "published": "2022-05-24T17:25:24Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2020-2035"
    },
    {
      "type": "WEB",
      "url": "https://security.paloaltonetworks.com/CVE-2020-2035"
    },
    {
      "type": "WEB",
      "url": "https://www.mnemonic.no/blog/introducing-snicat"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

cve-2020-2035

Vulnerability from cvelistv5

Published

2020-08-12 17:05

Modified

2024-09-17 04:10

Severity ?

3.0 (Low) - CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:N/I:L/A:N

Summary

PAN-OS: URL filtering policy is not enforced on TLS handshakes for decrypted HTTPS sessions

References

▼	URL	Tags
	https://security.paloaltonetworks.com/CVE-2020-2035	x_refsource_MISC
	https://www.mnemonic.no/blog/introducing-snicat/	x_refsource_MISC

Impacted products

▼	Vendor	Product
	Palo Alto Networks	PAN-OS

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "providerMetadata": {
          "dateUpdated": "2024-08-04T06:54:00.688Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "tags": [
              "x_refsource_MISC",
              "x_transferred"
            ],
            "url": "https://security.paloaltonetworks.com/CVE-2020-2035"
          },
          {
            "tags": [
              "x_refsource_MISC",
              "x_transferred"
            ],
            "url": "https://www.mnemonic.no/blog/introducing-snicat/"
          }
        ],
        "title": "CVE Program Container"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "PAN-OS",
          "vendor": "Palo Alto Networks",
          "versions": [
            {
              "status": "affected",
              "version": "8.1.*"
            },
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              "status": "affected",
              "version": "9.0.*"
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            {
              "status": "affected",
              "version": "9.1.*"
            },
            {
              "status": "affected",
              "version": "10.0.*"
            },
            {
              "status": "affected",
              "version": "10.1.*"
            }
          ]
        }
      ],
      "configurations": [
        {
          "lang": "en",
          "value": "This URL filtering policy evasion situation is only applicable when the following conditions are true:\n\n1. A host in the network is already compromised by a malicious actor.\n\n2. The PAN-OS configuration must have the SSL/TLS Decryption Forward Proxy feature enabled for the specific traffic that the attacker controls.\n\n3. There is no other security device in the chain that performs URL Filtering or can block access to malicious URLs or IP-addresses on the encrypted SSL/TLS traffic."
        }
      ],
      "credits": [
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          "value": "Palo Alto Networks thanks Morten Marstrander and Matteo Malvica from mnemonic AS for discovering and reporting this issue."
        }
      ],
      "datePublic": "2020-08-12T00:00:00",
      "descriptions": [
        {
          "lang": "en",
          "value": "When SSL/TLS Forward Proxy Decryption mode has been configured to decrypt the web transactions, the PAN-OS URL filtering feature inspects the HTTP Host and URL path headers for policy enforcement on the decrypted HTTPS web transactions but does not consider Server Name Indication (SNI) field within the TLS Client Hello handshake. This allows a compromised host in a protected network to evade any security policy that uses URL filtering on a firewall configured with SSL Decryption in the Forward Proxy mode. A malicious actor can then use this technique to evade detection of communication on the TLS handshake phase between a compromised host and a remote malicious server. This technique does not increase the risk of a host being compromised in the network. It does not impact the confidentiality or availability of a firewall. This is considered to have a low impact on the integrity of the firewall because the firewall fails to enforce a policy on certain traffic that should have been blocked. This issue does not impact the URL filtering policy enforcement on clear text or encrypted web transactions. This technique can be used only after a malicious actor has compromised a host in the protected network and the TLS/SSL Decryption feature is enabled for the traffic that the attacker controls. Palo Alto Networks is not aware of any malware that uses this technique to exfiltrate data. This issue is applicable to all current versions of PAN-OS. This issue does not impact Panorama or WF-500 appliances."
        }
      ],
      "exploits": [
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      "metrics": [
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          "cvssV3_1": {
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          "url": "https://www.mnemonic.no/blog/introducing-snicat/"
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        }
      ],
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      },
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          "time": "2021-03-03T00:00:00",
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        },
        {
          "lang": "en",
          "time": "2021-06-09T00:00:00",
          "value": "Updated impacted versions to include PAN-OS 10.1"
        }
      ],
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        }
      ],
      "x_generator": {
        "engine": "Vulnogram 0.0.9"
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      "x_legacyV4Record": {
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          "ASSIGNER": "psirt@paloaltonetworks.com",
          "DATE_PUBLIC": "2020-08-12T16:00:00.000Z",
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          "STATE": "PUBLIC",
          "TITLE": "PAN-OS: URL filtering policy is not enforced on TLS handshakes for decrypted HTTPS sessions"
        },
        "affects": {
          "vendor": {
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              {
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          }
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        "description": {
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              "value": "When SSL/TLS Forward Proxy Decryption mode has been configured to decrypt the web transactions, the PAN-OS URL filtering feature inspects the HTTP Host and URL path headers for policy enforcement on the decrypted HTTPS web transactions but does not consider Server Name Indication (SNI) field within the TLS Client Hello handshake. This allows a compromised host in a protected network to evade any security policy that uses URL filtering on a firewall configured with SSL Decryption in the Forward Proxy mode. A malicious actor can then use this technique to evade detection of communication on the TLS handshake phase between a compromised host and a remote malicious server. This technique does not increase the risk of a host being compromised in the network. It does not impact the confidentiality or availability of a firewall. This is considered to have a low impact on the integrity of the firewall because the firewall fails to enforce a policy on certain traffic that should have been blocked. This issue does not impact the URL filtering policy enforcement on clear text or encrypted web transactions. This technique can be used only after a malicious actor has compromised a host in the protected network and the TLS/SSL Decryption feature is enabled for the traffic that the attacker controls. Palo Alto Networks is not aware of any malware that uses this technique to exfiltrate data. This issue is applicable to all current versions of PAN-OS. This issue does not impact Panorama or WF-500 appliances."
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          }
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    "datePublished": "2020-08-12T17:05:15.346529Z",
    "dateReserved": "2019-12-04T00:00:00",
    "dateUpdated": "2024-09-17T04:10:07.790Z",
    "state": "PUBLISHED"
  },
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  "dataVersion": "5.1"
}

Sightings

Author	Source	Type	Date

Nomenclature

Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
Confirmed: The vulnerability is confirmed from an analyst perspective.
Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
Patched: This vulnerability was successfully patched by the user reporting the sighting.
Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
Not confirmed: The user expresses doubt about the veracity of the vulnerability.
Not patched: This vulnerability was not successfully patched by the user reporting the sighting.

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