CVE-2020-2035

What it is

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.

At a glance

Exploitability

Can be exploited over the network with an admin-level account. Limited direct impact.

Exploit odds

0.8% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2020-08-12 17:15 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-06-17 03:11 UTC Last updatedMost recent change to the record

Why it ranks here

• Exploited in the wild: no, CISA does not list it.
• Exploit odds: 0.8% in the next 30 days (EPSS).
• Severity: 3.0 LOW (CVSS).
• Fix: a patch or advisory is linked.

Details

Published

2020-08-12 17:15 UTC

Last modified

2026-06-17 03:11 UTC

Exploit probability

0.8% · EPSS, next 30 days

Weakness

CWE-20 · Improper input validation

Record status

Modified

Affected

• Paloaltonetworks pan-os

Attack profile CVSS 3.1 · 3.0

Attack vector

Network

Complexity

High

Privileges needed

High

User interaction

None

Scope

Changed

Confidentiality

None

Integrity

Low

Availability

None

Is it in your code?

Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.

Read https://cve-list.com/agent/cve/CVE-2020-2035.md and follow it. Check whether this project is affected by CVE-2020-2035. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.

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