GlobalProtect App: Buffer Overflow Vulnerability during UDP Tunnel Handshake

Primary CVSS: v4.0 5.2 MEDIUM from [email protected]

CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:N/R:U/V:D/RE:M/U:Amber

EPSS: 0.001640000 probability, percentile 0.060770000 (date 2026-08-18)

Problem Types: CWE-787 | CWE-787 CWE-787 Out-of-bounds Write

Discovery Credit

CNA: our internal security research teams (en)

Solutions

CNA: VERSION MINOR VERSION SUGGESTED SOLUTION GlobalProtect App 6.3/6.2 on Linux 6.2.0 through 6.3.3-h14 Upgrade to 6.3.3-h15 or later. GlobalProtect App 6.0 on Linux 6.0.0 through 6.0.14 Upgrade to 6.0.15 or later. GlobalProtect App 6.3 on macOS 6.3.0 through 6.3.3-h13 Upgrade to 6.3.3-h14 (6.3.3-1121) or later. GlobalProtect App 6.2 on macOS 6.2.0 through 6.2.8-h12 Upgrade to 6.2.8-h13 (6.2.8-1045) or later. GlobalProtect App 6.0 on macOS 6.0.0 through 6.0.14 Upgrade to 6.0.15 or later. GlobalProtect App 6.3 on Windows 6.3.0 through 6.3.3-h13 Upgrade to 6.3.3-h14 (6.3.3-1121) or later. GlobalProtect App 6.2 on Windows 6.2.0 through 6.2.8-h12 Upgrade to 6.2.8-h13 (6.2.8-1045) or later. GlobalProtect App 6.0 on Windows 6.0.0 through 6.0.14 Upgrade to 6.0.15 or later. GlobalProtect App 6.3/6.1 on iOS 6.1.0 through 6.3.4 Upgrade to 6.3.5 or later. GlobalProtect App 6.0 on iOS 6.0.0 through 6.0.14 Upgrade to 6.0.15 or later. GlobalProtect App 6.3/6.1 on Android 6.1.0 through 6.3.4 Upgrade to 6.3.5 or later. GlobalProtect App 6.0 on Android 6.0.0 through 6.0.14 Upgrade to 6.0.15 or later. GlobalProtect App 6.3/6.1 on ChromeOS 6.1.0 through 6.3.4 Upgrade to 6.3.5 or later. GlobalProtect App 6.0 on ChromeOS 6.0.0 through 6.0.14 Upgrade to 6.0.15 or later.

Workarounds

CNA: Customers can mitigate the risk of this issue by taking either of the following three actions: 1. Enforce SSL-Only VPN Connections: Modify your GlobalProtect Portal configurations to disable IPSec/UDP tunneling, forcing the client applications to connect exclusively via SSL VPN mode. Customer can configure Connect with SSL Only (https://docs.paloaltonetworks.com/globalprotect/administration/globalprotect-portals/customize-the-globalprotect-app) tunnel by configuring ' Advanced Control for Tunnel Mode Behavior' on GlobalProtect Portal Network > Portal > Agent Configuration> Advanced Control for Tunnel Mode Behavior 2. Customers can configure SSL only tunnel protocol by un-checking 'Enable IPSec (https://docs.paloaltonetworks.com/ngfw/help/10-2/globalprotect/network-globalprotect-gateways/globalprotect-gateways-agent-tab/tunnel-settings-tab)' on GlobalProtect gateway at Network > Gateway > Agent > Tunnel Setting > Enable IPSec 3. Workaround for new and existing GlobalProtect app >= 6.2.8 or GlobalProtect app >= 6.3.3 installations on Windows and macOS GlobalProtect 6.2.8 and GlobalProtect app 6.3.3 on Windows and macOS introduce a new configuration Enable Strict Certificate Check (https://docs.paloaltonetworks.com/platform-explorer?productCategoryTags=pan%3Aproductcategory%2Fglobalprotect) which enables certificate checks required to mitigate this issue on Windows and macOS. This configuration only takes effect after the first connection between the GlobalProtect client and the GlobalProtect portal. Therefore the first connection is not protected. To ensure that the first connection is also protected, additionally follow the steps noted below for GlobalProtect < 6.2.8. This configuration option is currently not available for the GlobalProtect app on platforms other than Windows and macOS. Workaround for new and existing GlobalProtect app < 6.2.8 or GlobalProtect app < 6.3.3 installations on macOS 1. Use Xcode to edit the com.paloaltonetworks.GlobalProtect.settings.plist file (https://docs.paloaltonetworks.com/globalprotect/10-1/globalprotect-admin/globalprotect-apps/deploy-app-settings-transparently/deploy-app-settings-to-mac-endpoints/deploy-app-settings-in-the-mac-plist) in /Library/Preferences. 2. Add a "Settings" section if it does not exist within the GlobalProtect section. 3. Within the "Settings" section, add the full-chain-cert-verify key and set the string value to yes 4. Restart macOS.  <key>GlobalProtect</key>  <dict>   (removed for brevity)   <key>Settings</key>   <dict>   <key>full-chain-cert-verify</key>   <string>yes</string>  </dict> </dict>    Workaround for new and existing GlobalProtect app installations on Linux      1. Create the /opt/paloaltonetworks/globalprotect/pangps.xml pre-deployment configuration file.      2. Add the pre-deployment settings to the pangps.xml file           <GlobalProtect>         <Settings>          <full-chain-cert-verify>yes</full-chain-cert-verify>        </Settings       </GlobalProtect>     Workaround for new and existing GlobalProtect app installations on Android, iOS and ChromeOS     Customers can use their endpoint mobile device management (MDM) tools to apply the following changes       1. Set the key "full-chain-cert-verify"="yes".

Exploits

CNA: Palo Alto Networks is not aware of any malicious exploitation of this issue.