Security readout for executives and security teams
Plain-English summary
This flaw can let someone who already has basic code execution on a Windows endpoint weaken Trend Micro protection and gain higher privileges. Because CISA lists CVE-2020-24557 as known exploited, organizations running affected Trend Micro endpoint products should treat it as urgent operational risk, not theoretical exposure.
Executive priority
Prioritize remediation for affected Trend Micro-managed Windows endpoints, especially high-value workstations and servers. KEV listing means exploitation has been observed, and successful abuse can undermine security controls while raising attacker privileges.
Technical view
CVE-2020-24557 is a local privilege escalation issue in Trend Micro Apex One and Worry-Free Business Security 10.0 SP1 on Windows. The described path involves manipulating a product folder, temporarily disabling protection, abusing a Windows function, and escalating privileges. CVSS is 7.8 with local access and low privileges required.
Likely exposure
Exposure is most likely on Windows endpoints running affected Trend Micro Apex One 2009, Apex One SaaS, or Worry-Free Business Security 10.0 SP1. Systems before Windows 10 version 1909 build 18363.719 are specifically noted as affected by the hard-link aspect.
Exploitation context
CISA KEV status supports known exploitation. The attacker must already be able to run low-privileged code locally, so this is most concerning after phishing, malware foothold, compromised user sessions, or lateral movement onto an endpoint.
Researcher notes
Available evidence describes a local privilege escalation tied to product folder manipulation and Windows hard-link behavior. Public bundle details do not include safe reproduction steps or exact fixed build numbers, so validation should rely on vendor advisory status, inventory, and telemetry.
Mitigation direction
- Review Trend Micro advisories 000263632 and 000267260 for official fixes and deployment guidance.
- Patch or update affected Trend Micro endpoint products according to vendor instructions.
- Verify Windows endpoints meet the noted Windows 10 1909 build 18363.719 mitigation where applicable.
- Harden endpoint user privileges to reduce low-privileged code execution opportunities.
- Monitor for endpoint protection tampering or unexpected service disablement.
Validation and detection
- Inventory Windows endpoints running Trend Micro Apex One or Worry-Free Business Security.
- Identify affected versions: Apex One 2009/SaaS and Worry-Free Business Security 10.0 SP1.
- Check Windows build levels against the 1909 build 18363.719 note in the CVE description.
- Confirm Trend Micro vendor fixes or updates are applied through management console reporting.
- Review EDR or endpoint logs for security product disablement events.
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.
Privilege behavior lookup
The CVE wording references privilege impact, so privilege escalation and authorization behavior review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2020-24557 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
- Yes
- Published
Vector: CVSS:3.1/AV:L/AC:L/PR:L/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.
CISA KEV status
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:H/A:H1.85.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
7.8HighVector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://success.trendmicro.com/solution/000263632CVE reference · x_refsource_MISC
- https://www.zerodayinitiative.com/advisories/ZDI-20-1094/CVE reference · x_refsource_MISC
- https://success.trendmicro.com/solution/000267260CVE reference · x_refsource_MISC
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-24557CVE reference · government-resource
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.