Security readout for executives and security teams
Plain-English summary
CVE-2020-17091 is a high-severity Microsoft Teams remote code execution vulnerability. The supplied scoring requires user interaction and a local attack vector, but successful exploitation could compromise confidentiality, integrity, and availability. The bundle does not specify affected Teams versions, so inventory and vendor guidance are essential.
Executive priority
Treat this as a high-priority endpoint hygiene issue, not an emergency based on the supplied evidence. Confirm Teams update status and close gaps on unmanaged systems.
Technical view
The CVE is classified as CWE-94 with CVSS 3.1 score 7.8: AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H. Microsoft Teams is the only affected product named. The CVSS metadata indicates an official fix exists, but the supplied bundle does not include version-specific remediation details.
Likely exposure
Organizations with Microsoft Teams installed on endpoints may have exposure, especially if systems were not updated after the November 2020 Microsoft advisory. The bundle lists affected versions as N/A, so exact exposure cannot be determined from these sources alone.
Exploitation context
The bundle does not show CISA KEV listing or cited evidence of active exploitation. The CVSS vector indicates user interaction is required and exploit maturity is unproven, so urgency is driven by potential impact rather than confirmed exploitation.
Researcher notes
Evidence is limited to CVE/MSRC metadata. The source bundle gives no affected version matrix, root-cause detail, exploit narrative, or detection artifacts. Avoid assuming exploitation paths beyond the CVSS properties and CWE-94 classification.
Mitigation direction
- Review Microsoft’s CVE-2020-17091 advisory for affected build and update guidance.
- Update Microsoft Teams using vendor-supported channels.
- Prioritize endpoints with outdated Teams installations.
- Remove unsupported or unmanaged Teams installations where business use is absent.
Validation and detection
- Inventory Microsoft Teams installations across managed endpoints.
- Compare installed Teams builds against Microsoft advisory guidance.
- Confirm endpoint update telemetry shows Teams remediation completed.
- Review vulnerability scanner results for CVE-2020-17091 coverage.
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-94: Code execution behavior lookup
Code execution and unsafe deserialization weaknesses often justify reviewing execution behavior and process telemetry. 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-2020-17091 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
- 7.8 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/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.
SSVC decision data
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:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C1.85.9microsoftVulnerability scoring details
Base CVSS 3.1 score
7.8HighVector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
Source materials
- CVE List V5 sourceCVE List V5
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-17091CVE reference, microsoft · 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 Control of Generation of Code ('Code Injection')
Improper Control of Generation of Code ('Code Injection') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.