CVE-2020-2021

CRITICAL KEV RANSOMWARE

PAN-OS 8.0.x < 8.0.20 - Unauthenticated SAML Authentication Bypass via Improper Signature Verification

Title source: llm
STIX 2.1

Exploitation Summary

CVE-2020-2021 is actively exploited and listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, added March 25, 2022, with confirmed use in ransomware campaigns. EIP tracks 1 public exploit.

AI-analyzed exploit summary The repository claims to be a PoC for CVE-2020-2021 but contains no actual exploit code. Instead, it directs users to download and execute a script from a bit.ly URL, which is a common tactic for distributing malware or fake exploits.

Description

When Security Assertion Markup Language (SAML) authentication is enabled and the 'Validate Identity Provider Certificate' option is disabled (unchecked), improper verification of signatures in PAN-OS SAML authentication enables an unauthenticated network-based attacker to access protected resources. The attacker must have network access to the vulnerable server to exploit this vulnerability. This issue affects PAN-OS 9.1 versions earlier than PAN-OS 9.1.3; PAN-OS 9.0 versions earlier than PAN-OS 9.0.9; PAN-OS 8.1 versions earlier than PAN-OS 8.1.15, and all versions of PAN-OS 8.0 (EOL). This issue does not affect PAN-OS 7.1. This issue cannot be exploited if SAML is not used for authentication. This issue cannot be exploited if the 'Validate Identity Provider Certificate' option is enabled (checked) in the SAML Identity Provider Server Profile. Resources that can be protected by SAML-based single sign-on (SSO) authentication are: GlobalProtect Gateway, GlobalProtect Portal, GlobalProtect Clientless VPN, Authentication and Captive Portal, PAN-OS next-generation firewalls (PA-Series, VM-Series) and Panorama web interfaces, Prisma Access In the case of GlobalProtect Gateways, GlobalProtect Portal, Clientless VPN, Captive Portal, and Prisma Access, an unauthenticated attacker with network access to the affected servers can gain access to protected resources if allowed by configured authentication and Security policies. There is no impact on the integrity and availability of the gateway, portal or VPN server. An attacker cannot inspect or tamper with sessions of regular users. In the worst case, this is a critical severity vulnerability with a CVSS Base Score of 10.0 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N). In the case of PAN-OS and Panorama web interfaces, this issue allows an unauthenticated attacker with network access to the PAN-OS or Panorama web interfaces to log in as an administrator and perform administrative actions. In the worst-case scenario, this is a critical severity vulnerability with a CVSS Base Score of 10.0 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H). If the web interfaces are only accessible to a restricted management network, then the issue is lowered to a CVSS Base Score of 9.6 (CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H). Palo Alto Networks is not aware of any malicious attempts to exploit this vulnerability.

Exploits (1)

inthewild SUSPICIOUS
poc
https://github.com/mr-r3b00t/cve-2020-2021

The repository claims to be a PoC for CVE-2020-2021 but contains no actual exploit code. Instead, it directs users to download and execute a script from a bit.ly URL, which is a common tactic for distributing malware or fake exploits.

Classification
Suspicious 95%
Attack Type
Other
Complexity
Trivial
Reliability
Theoretical
Target: unknown
No auth needed
Prerequisites: none
devstral-2 · analyzed Feb 23, 2026 Full analysis →

References (2)

Core 2

Scores

CVSS v3 10.0
EPSS 0.1896
EPSS Percentile 95.5%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

CISA SSVC

Vulnrichment
Exploitation active
Automatable yes
Technical Impact total

Details

CISA KEV 2022-03-25
VulnCheck KEV 2020-09-17
InTheWild.io 2021-10-21
ENISA EUVD EUVD-2020-22049
Ransomware Use Confirmed
CWE
CWE-347
Status published
Products (1)
paloaltonetworks/pan-os 8.0.0 - 8.0.20
Published Jun 29, 2020
KEV Added Mar 25, 2022
Tracked Since Feb 18, 2026