Security readout for executives and security teams
Plain-English summary
CVE-2021-28318 is a Windows GDI+ information disclosure issue. A local authenticated user could potentially expose sensitive information from affected Windows systems. The source bundle rates it medium, with high confidentiality impact but no integrity or availability impact.
Executive priority
Treat this as a moderate patch-management item. It does not have cited active exploitation in the bundle, but it can expose sensitive information after local access. Prioritize remaining legacy Windows systems and servers because unsupported or delayed patching increases residual risk.
Technical view
The CVSS 3.1 vector is AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N, indicating local access, low complexity, low privileges, no user interaction, unchanged scope, and high confidentiality impact. Microsoft lists multiple Windows client and server releases as affected.
Likely exposure
Exposure is most relevant where affected Windows 7, 8.1, 10, Windows Server 2008, 2016, 2019, and related Server Core/version releases remain unpatched. The provided CVSS vector does not describe remote reachability.
Exploitation context
The bundle marks KEV as false and provides no cited evidence of active exploitation. Exploitation is characterized as local and authenticated by the CVSS vector, so this is more likely a post-access information disclosure risk than an initial-entry issue.
Researcher notes
The available evidence is sparse: the description only states Windows GDI+ information disclosure, with no CWE, root-cause detail, exploit narrative, or mitigation beyond Microsoft guidance. Some affected CPE entries appear duplicated or inconsistent, so validate exact applicability against MSRC.
Mitigation direction
- Review Microsoft’s CVE-2021-28318 guidance for applicable security updates.
- Prioritize patching affected Windows endpoints and servers still in production.
- Verify extended support status for Windows 7 and Server 2008 assets.
- Reduce local user access where patching is delayed.
- Track unsupported systems for upgrade or isolation decisions.
Validation and detection
- Inventory Windows versions listed in the source bundle across endpoints and servers.
- Confirm installed Microsoft security updates against the MSRC advisory.
- Flag affected Server Core installations separately for operations review.
- Validate that legacy Windows 7 and Server 2008 systems are covered.
- Document any systems awaiting vendor guidance or compensating controls.
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-2021-28318 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:U/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:U/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:U/RL:O/RC:C
Source materials
- CVE List V5 sourceCVE List V5
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-28318CVE 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.