Security readout for executives and security teams
Plain-English summary
CVE-2020-16879 is a Windows Projected Filesystem information disclosure issue. A logged-in attacker could run a specially crafted application to obtain information that may help further compromise the user’s system. It is not described as remote code execution or privilege escalation.
Executive priority
Handle through normal patch management, with priority for shared systems, servers, and endpoints where local users are less trusted. Business risk is mainly confidentiality loss that could support later compromise, not direct remote takeover.
Technical view
The vulnerability occurs when Windows Projected Filesystem improperly handles file redirections. CVSS 3.1 is 5.5: local attack vector, low complexity, low privileges required, no user interaction, high confidentiality impact, no integrity or availability impact.
Likely exposure
Exposure is likely limited to affected Windows 10 and Windows Server builds listed by Microsoft, including versions 1809, 1903, 1909, 2004, and Windows Server 2019 variants. Systems allowing untrusted local users or applications are higher priority.
Exploitation context
The source states exploitation requires the attacker to first log on locally and then run a specially crafted application. The bundle does not identify active exploitation, and KEV status is false, so treat exploitation as possible but not confirmed in the wild.
Researcher notes
Evidence supports a local information disclosure flaw in Projected Filesystem redirection handling. Microsoft states the update corrects that handling. Some CPE entries in the bundle appear duplicated or broad, so validate exact platform applicability against MSRC before scoping exceptions.
Mitigation direction
- Apply Microsoft’s security update for CVE-2020-16879 to affected Windows builds.
- Check Microsoft guidance for exact KB applicability and supersedence.
- Prioritize systems where untrusted local users can execute applications.
- Restrict unnecessary local logon and application execution rights.
Validation and detection
- Inventory Windows 10 and Windows Server versions against the affected product list.
- Verify relevant Microsoft security updates are installed on affected assets.
- Use vulnerability management tooling to confirm CVE-2020-16879 is no longer detected.
- Review local user access on exposed workstations and servers.
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.
CVE-2020-16879 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:H/I:N/A:N/E:P/RL:O/RC:C
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:H/I:N/A:N/E:P/RL:O/RC:C1.83.6Primary 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:H/I:N/A:N/E:P/RL:O/RC:C
Source materials
- CVE List V5 sourceCVE List V5
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-16879CVE 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.