Command Injection in Microsoft Outlook (CVE-2026-42893)
Summary
Command injection in Microsoft Outlook (CVE-2026-42893). Data can be tampered with by attackers.
Original description
The description as published by the source.
Improper neutralization of special elements used in a command ('command injection') in M365 Copilot allows an unauthorized attacker to perform tampering over a network.
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-2026-42893 has been found in Microsoft Outlook.
Data can be tampered with by attackers. CVSS score: 7.4/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Microsoft Outlook CVE-2026-42893" on the vendor's site.
CVE-2026-42893 (Microsoft Outlook) — CWE-77 / CVSS v3 7.4
Attack vector: remote (network-reachable) / 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.
A vulnerability (CWE-77) exists in Microsoft Outlook.
Check the vendor advisory for the affected versions of Microsoft Outlook.
Severity: High (CVSS 7.4/10). Data can be tampered with by attackers.
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. Run grep -r 'Outlook' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'Outlook' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
Outlookを grep し、稼働しているサービス・バージョンを把握する。 -
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 secure@microsoft.com
- web nvd.nist.gov
- web github.com