Out-of-Bounds Write in Microsoft 365 Apps (CVE-2020-16918)
Summary
Out-of-bounds write in Microsoft 365 Apps (CVE-2020-16918). Successful exploitation can lead to full system takeover.
Original description
The description as published by the source.
A remote code execution vulnerability exists when the Base3D rendering engine improperly handles memory.An attacker who successfully exploited the vulnerability would gain execution on a victim system.The security update addresses the vulnerability by correcting how the Base3D rendering engine handles memory., aka 'Base3D Remote Code Execution Vulnerability'. This CVE ID is unique from CVE-2020-17003.
Source: GitHub Security Advisories (Global) NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2020-16918 has been found in Microsoft 365 Apps.
Successful exploitation can lead to full system takeover. CVSS score: 7.8/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Microsoft 365 Apps CVE-2020-16918" on the vendor's site.
CVE-2020-16918 (Microsoft 365 Apps) — CWE-787 / CVSS v3 7.8
Attack vector: local / unauthenticated
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
Out-of-bounds write (CWE-787) exists in Microsoft 365 Apps.
Check the vendor advisory for the affected versions of Microsoft 365 Apps.
Severity: High (CVSS 7.8/10). Successful exploitation can lead to full system takeover.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Audit SBOM/dependencies to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
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1Identify exposure identify
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで Microsoft 365 Apps を使っているサービスとバージョンを洗い出す。
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2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
References
- patch portal.msrc.microsoft.com
- web nvd.nist.gov
- web github.com