CVE-2021-3057: GlobalProtect App: Buffer Overflow Vulnerability When Connecting to Portal or Gateway

Severity: critical (CVSS 9.3 v2.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-10-13 · updated 2026-06-17
Weakness: CWE-121

Description

A stack-based buffer overflow vulnerability exists in the Palo Alto Networks GlobalProtect app that enables a man-in-the-middle attacker to disrupt system processes and potentially execute arbitrary code with SYSTEM privileges. This issue impacts: GlobalProtect app 5.1 versions earlier than GlobalProtect app 5.1.9 on Windows; GlobalProtect app 5.2 versions earlier than GlobalProtect app 5.2.8 on Windows; GlobalProtect app 5.2 versions earlier than GlobalProtect app 5.2.8 on the Universal Windows Platform; GlobalProtect app 5.3 versions earlier than GlobalProtect app 5.3.1 on Linux.

Affected products

Palo Alto Networks GlobalProtect App: from 5.0 through 5.0.8; from 5.0 through 5.0.9; from 5.0 through 5.0.10; from 5.1 through 5.1.1; from 5.1 before 5.1.9; from 5.1.0 through 5.1.4 — fixed in 5.1.9, 5.2.8, 5.3.1
Palo Alto Networks GlobalProtect App: from 5.1 before 5.1.9; from 5.2 before 5.2.8 — fixed in 5.1.9, 5.2.8

How to fix

Upgrade to a fixed version: Palo Alto Networks GlobalProtect App 5.1.9, 5.2.8, 5.3.1; Palo Alto Networks GlobalProtect App 5.1.9, 5.2.8. Check the vendor advisory for mitigations.

References

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