Security readout for executives and security teams
Plain-English summary
This vulnerability can let a low-privileged Windows user crash a machine running an affected Palo Alto Networks GlobalProtect VPN client, causing a blue screen. It is an availability issue, not a data theft or remote takeover issue based on the supplied sources.
Executive priority
Treat this as a moderate endpoint availability risk. It is unlikely to justify emergency incident response without exploitation evidence, but VPN client upgrades should be prioritized in routine endpoint patch cycles.
Technical view
CVE-2021-3038 is a local denial-of-service flaw in Palo Alto Networks GlobalProtect App for Windows. A limited Windows user can send crafted input to the app, triggering a BSOD. Affected versions are 5.1 before 5.1.8 and 5.2 before 5.2.4.
Likely exposure
Exposure is limited to Windows endpoints running GlobalProtect App 5.1 earlier than 5.1.8 or 5.2 earlier than 5.2.4. Systems without the Windows GlobalProtect client, or already upgraded beyond those versions, are not indicated as affected in the supplied bundle.
Exploitation context
The CVSS vector is local, low complexity, low privileges required, and no user interaction. The bundle marks KEV as false, and no supplied source states active exploitation. Practical impact is local disruption of endpoint availability.
Researcher notes
The issue maps to CWE-20 and CWE-248. CVSS 3.1 is 5.5 with AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H, aligning with local low-privilege availability impact only. Supplied evidence does not support confidentiality or integrity impact.
Mitigation direction
- Update GlobalProtect 5.1 clients to 5.1.8 or later.
- Update GlobalProtect 5.2 clients to 5.2.4 or later.
- Check Palo Alto Networks guidance for supported upgrade paths.
- Prioritize endpoints where VPN availability affects operations.
Validation and detection
- Inventory Windows endpoints running Palo Alto Networks GlobalProtect App.
- Flag GlobalProtect 5.1 versions earlier than 5.1.8.
- Flag GlobalProtect 5.2 versions earlier than 5.2.4.
- Confirm upgraded endpoints report fixed or later versions.
- Review endpoint crash history where affected versions remain.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-20: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCWE-248: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2021-3038 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 5.5 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H1.83.6Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
5.5MediumVector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://security.paloaltonetworks.com/CVE-2021-3038CVE reference · x_refsource_MISC
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Improper Input Validation
Improper Input Validation represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.
Uncaught Exception
Uncaught Exception represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.