Security readout for executives and security teams
Plain-English summary
CVE-2021-3057 affects Palo Alto Networks GlobalProtect App. A network attacker positioned between a user and the portal or gateway could crash system processes and may run code with SYSTEM privileges. This is high urgency for organizations with affected GlobalProtect clients, especially VPN-heavy workforces.
Executive priority
Treat as a high-priority endpoint VPN client update. The required attacker position reduces likelihood, but SYSTEM-level code execution potential makes delayed remediation risky for remote access populations.
Technical view
The issue is a stack-based buffer overflow in GlobalProtect App when connecting to a portal or gateway. A man-in-the-middle attacker can trigger process disruption and potentially arbitrary code execution as SYSTEM. Affected versions include Windows 5.1 before 5.1.9, Windows/UWP 5.2 before 5.2.8, and Linux 5.3 before 5.3.1.
Likely exposure
Exposure is limited to endpoints running the named vulnerable GlobalProtect App versions. The attack requires a man-in-the-middle position during portal or gateway connection, but needs no privileges or user interaction per the CVSS vector.
Exploitation context
The source bundle does not show CISA KEV listing or cited active exploitation. Attack complexity is high because the attacker must be in a network position to intercept the GlobalProtect connection, but successful impact could be severe on the endpoint.
Researcher notes
CVSS 3.1 score is 8.1 with AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H. The vulnerability is CWE-121. Available evidence identifies affected version ranges and impact, but does not provide exploit details or proof of active exploitation.
Mitigation direction
- Upgrade Windows GlobalProtect 5.1 clients to 5.1.9 or later.
- Upgrade Windows and UWP 5.2 clients to 5.2.8 or later.
- Upgrade Linux 5.3 clients to 5.3.1 or later.
- Check Palo Alto Networks guidance for supported upgrade paths.
- Use endpoint management to enforce minimum GlobalProtect versions.
Validation and detection
- Inventory GlobalProtect App versions across managed endpoints.
- Confirm affected Windows, UWP, and Linux versions are absent.
- Verify software deployment catalogs contain only fixed versions.
- Review endpoint telemetry for GlobalProtect crashes or abnormal process failures.
- Document exceptions and remediation deadlines for unmanaged devices.
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-121: 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 lookupExecution behavior lookup
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2021-3057 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
- High
- CVSS
- 8.1 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/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:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H2.25.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
8.1HighVector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://security.paloaltonetworks.com/CVE-2021-3057CVE 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.
Stack-based Buffer Overflow
Stack-based Buffer Overflow represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.