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Full vulnerability report · 2020
CVE-2020-2050High confidence

PAN-OS: Authentication bypass vulnerability in GlobalProtect SSL VPN client certificate verification

Palo Alto Networks · PAN-OS

8.2HighCVSS 3.1
Recommended action
Within 7 days

High technical severity; prioritise exposed affected systems while verifying vendor guidance.

Patch available
R
Operational reassessment

Published severity in operational context

Open reassessment dashboard →
Published severityHighOperational priority:High, unchanged from published severity.unchanged

Evidence used

  • No CISA KEV confirmation is currently recorded.
  • The selected CVSS metric records a network-reachable, unauthenticated path with no user interaction.
  • EPSS is 1.03% for the current model date.

Compensating controls

  • Validate the affected product branch and deploy the verified fixed release.
  • Restrict the affected network interface to trusted sources where business-safe.
  • Monitor vendor guidance and exploitation sources for a material change.

Verification

  1. Confirm that the asset runs Palo Alto Networks PAN-OS and falls inside the recorded affected range.
  2. Verify the installed build against the product-specific fixed version after deployment.
  3. Validate exposure, authentication requirements and compensating controls in the actual environment.
  4. Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Mitigation target: Within 30 daysRemediation target: Within 180 days

This automated reassessment organises public evidence. It does not know asset exposure, business impact or control effectiveness and does not replace CVSS or a human risk decision.

Optional official sources

National CERT insights
?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.

Choose official national sources for this report. Each advisory shows its original language. Your selection is remembered on this device and included in shared links.

Official European source

ENISA European Vulnerability Database

Official EUVD identifiers, advisory evidence and known-exploited context. Missing fields are not treated as evidence of low risk.

1 current
ENISA EUVD identifier

EUVD-2020-22076

No EUVD known-exploited evidence

ENISA has published the identifier mapping but no EUVD description has been stored yet.

EUVD state
Present in the current official mapping
Known exploitation
Not present in the current ENISA EUVD known-exploited dataset. This is not proof of no exploitation.
ENISA score
Not supplied in the stored EUVD record
Advisory evidence
No linked advisory details stored yet
Recommended actionWithin 7 days

High technical severity; prioritise exposed affected systems while verifying vendor guidance.

Patch available
01

What, why and how

An authentication bypass vulnerability exists in the GlobalProtect SSL VPN component of Palo Alto Networks PAN-OS software that allows an attacker to bypass all client certificate checks with an invalid certificate. A remote attacker can successfully authenticate as any user and gain access to restricted VPN network resources when the gateway or portal is configured to rely entirely on certificate-based authentication. Impacted features that use SSL VPN with client certificate verification are: GlobalProtect Gateway, GlobalProtect Portal, GlobalProtect Clientless VPN In configurations where client certificate verification is used in conjunction with other authentication methods, the protections added by the certificate check are ignored as a result of this issue. This issue impacts: PAN-OS 8.1 versions earlier than PAN-OS 8.1.17; PAN-OS 9.0 versions earlier than PAN-OS 9.0.11; PAN-OS 9.1 versions earlier than PAN-OS 9.1.5; PAN-OS 10.0 versions earlier than PAN-OS 10.0.1.

What

An authentication bypass vulnerability exists in the GlobalProtect SSL VPN component of Palo Alto Networks PAN-OS software that allows an attacker to bypass all client certificate checks with an invalid certificate. A remote attacker can successfully authenticate as any user and gain access to restricted VPN network resources when the gateway or portal is configured to rely entirely on certificate-based authentication. Impacted features that use SSL VPN with client certificate verification are: GlobalProtect Gateway, GlobalProtect Portal, GlobalProtect Clientless VPN In configurations where client certificate verification is used in conjunction with other authentication methods, the protections added by the certificate check are ignored as a result of this issue. This issue impacts: PAN-OS 8.1 versions earlier than PAN-OS 8.1.17; PAN-OS 9.0 versions earlier than PAN-OS 9.0.11; PAN-OS 9.1 versions earlier than PAN-OS 9.1.5; PAN-OS 10.0 versions earlier than PAN-OS 10.0.1.

Why

The product does not perform or incorrectly performs an authorization check when an actor attempts to access a resource or perform an action.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may bypass an access boundary or take over an account.

What

An authentication bypass vulnerability exists in the GlobalProtect SSL VPN component of Palo Alto Networks PAN-OS software that allows an attacker to bypass all client certificate checks with an invalid certificate. A remote attacker can successfully authenticate as any user and gain access to restricted VPN network resources when the gateway or portal is configured to rely entirely on certificate-based authentication. Impacted features that use SSL VPN with client certificate verification are: GlobalProtect Gateway, GlobalProtect Portal, GlobalProtect Clientless VPN In configurations where client certificate verification is used in conjunction with other authentication methods, the protections added by the certificate check are ignored as a result of this issue. This issue impacts: PAN-OS 8.1 versions earlier than PAN-OS 8.1.17; PAN-OS 9.0 versions earlier than PAN-OS 9.0.11; PAN-OS 9.1 versions earlier than PAN-OS 9.1.5; PAN-OS 10.0 versions earlier than PAN-OS 10.0.1.

Why

The product does not perform or incorrectly performs an authorization check when an actor attempts to access a resource or perform an action.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may bypass an access boundary or take over an account.

02

Exploit reality and attack path

CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.

Observed exploitation
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
No confirmed evidence

No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.

Public PoC / exploit material
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
None recorded

No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.

Likely attack path
a network path → Improper Authorization → bypass an access boundary or take over an account
Attack surface
Network
Privileges required
None: unauthenticated exploitation is possible
User interaction
None
Attack complexity
Low: no specialised conditions are recorded
Security boundary
Unchanged: impact remains within the vulnerable component's security authority
Weakness
?CWE means Common Weakness Enumeration: a standard category for the underlying weakness.
CWE-285 ↗

CWE-285: Improper Authorization. The product does not perform or incorrectly performs an authorization check when an actor attempts to access a resource or perform an action.

CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N

Common Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.

AVNetworkAttack vector: The vulnerable component can be reached over a network.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRNonePrivileges required: The attacker does not need an account or existing privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CHighConfidentiality impact: A successful attack can cause a major loss.ILowIntegrity impact: A successful attack can cause a limited loss.ANoneAvailability impact: No direct loss is represented by this metric.
Post-exploitation / living off the land
Stolen credentials, tokens and legitimate administration functions may provide continued access without deploying a large custom toolset.
NetworkUnauthenticatedCWE-285
A

Official authority intelligence

Only matched European and national findings are included. Language selectors and unavailable sources are omitted.

Canadian Centre for Cyber Security · English · AV20-424Palo Alto security advisory

PAN-OS: Authentication bypass https://security.paloaltonetworks.com/CVE-2020-2050 PAN-OS: Panorama session disclosure https://security.paloaltonetworks.com/CVE-2020-2022

Official advisory ↗
Cyber Security Agency of Singapore · English · CSA-SB-20201118Security Bulletin 18 Nov 2020

The Cyber Security Agency of Singapore included this CVE in its official Security Bulletin 18 Nov 2020, published on 18 November 2020. Open the linked bulletin for the product, severity and reference information published in that issue.

Official advisory ↗
CERT-FR · French · CERTFR-2020-AVI-745Multiples vulnérabilités dans Palo Alto Networks PAN-OS

De multiples vulnérabilités ont été découvertes dans Palo Alto  Networks PAN-OS. Elles permettent à un attaquant de provoquer un contournement de la politique de sécurité.

Official advisory ↗
CERT-FR · French · CERTFR-2020-AVI-730Multiples vulnérabilités dans Palo Alto PAN-OS

De multiples vulnérabilités ont été découvertes dans Palo Alto PAN-OS. Elles permettent à un attaquant de provoquer une exécution de code arbitraire à distance, un contournement de la politique de sécurité et une atteinte à la confidentialité des données.

Official advisory ↗
JVN iPedia · Japanese · JVNDB-2020-013439Palo Alto Networks PAN-OS ソフトウェアにおける認証に関する脆弱性

Palo Alto Networks PAN-OS ソフトウェアには、認証に関する脆弱性が存在します。

Official advisory ↗
03

Patch and workaround

Operational remediation based on structured source evidence.

Status
?Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change.
Patch available
Affected
PAN-OS: 8.1 < 8.1.17, 9.0 < 9.0.11, 9.1 < 9.1.5, 10.0 < 10.0.1
Fixed
This issue is fixed in PAN-OS 8.1.17, PAN-OS 9.0.11, PAN-OS 9.1.5, PAN-OS 10.0.1, and all later PAN-OS versions.
Action
Review the linked authoritative reference and apply the recorded fixed release appropriate to the affected product branch.
Workaround
No verified workaround is recorded. If business-safe, reduce exposure to the affected interface and allow only trusted sources until authoritative guidance is available.
04

Evidence and provenance

Published 12 Nov 2020 · Last source change 17 Sept 2024, 00:11 UTC · CWE-285 · Improper Authorization

CVE recordCVE.org · 5.1
CVSS sourceCNA
EPSS source
?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.
FIRST · tracked since 2026-08-14
European sourceENISA EUVD · EUVD-2020-22076
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceCNA
NVD statusNVD modified after enrichment

Core structured fields are present and their contributing authorities are shown above.

Material change intelligence

What changed after publication

View recent updates ↗
  1. Remediation statusRemediation status changed from Awaiting fix to Mitigation available.
    Before
    Awaiting fix
    After
    Mitigation available
    Canadian Centre for Cyber Security ↗
Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
CVE published
Remediation guidance recorded
ENISA EUVD · EUVD-2020-22076↗Canadian Centre for Cyber Security remediation guidance↗CVE authority or vendor reference↗Official CVE record (CNA and ADP data)↗NVD record↗
Technical terms and abbreviations used in this report
CVE
Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
CVSS
Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
EPSS
Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
CWE
Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
CNA
CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
CISA ADP
Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
NVD
National Vulnerability Database: NIST's enrichment service for CVE records.
CERT / CSIRT
A computer security incident response team that publishes warnings or coordinates incident response.
PoC
Proof of concept: public material that demonstrates or helps reproduce exploitation.
CSAF
Common Security Advisory Framework: a machine-readable format for security advisories.
LoTL
Living off the land: abuse of legitimate tools or system functions during an attack.
Free version - for non-commercial use only.CVE-2020-2050 · cve.blacktree.nl