Signal is active with 2 mentions in latest observed window
Recommended action window: Monitor and triage in normal cycle
NVD description
Deserialization of untrusted data in M365 Copilot allows an authorized attacker to execute code over a network.
Priority
LOW
Exploitation
NONE
PoC
NONE
Patch
AVAILABLE
Momentum
STABLE
If you run products in this scope, you should treat this CVE as relevant to your environment.
1 version affected across 1 product
| Date | Total | Labels |
|---|
| 2026-07-24 | 6 | Disclosure3General1Patch2 |
| 2026-07-27 | 2 | Disclosure1General1 |
#securityupdate #microsoft #定例外 2026. 7.23 Microsoft M365 Copilot のリモートでコードが実行される脆弱性 CVE-2026-50517 Security Vulnerability リリース日: - マイクロソフト https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-50517
Post summary
Microsoft has announced a remote code execution vulnerability (CVE‑2026‑50517) affecting M365 Copilot, providing a link to the security update guide but no PoC, exploit, or patch details.
CopilotのRCE、これは胃が痛い。 CVE-2026-50517は、M365 Copilotがuntrusted dataをDeserializationする処理の不備により、認証済みの攻撃者がnetwork経由でcode executionできる脆弱性だ。公開内容から実悪用までは確認できないが、現場で怖いのは端末の更新確認だけで終わること。 自分ならMicrosoft 365管理センターのMessage centerでテナント側の対応要否を照合し、Purview AuditをOperation=CopilotInteractionで検索する。AppIdentity、AppHost、AccessedResourcesを保存し、普段と異なる利用者や参照先を絞ってほしい。侵害を断定するログではないが、初動の母集団作りには効く。Copilot利用組織は確認手順として保存推奨。 #セキュリティ ソース: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-50517
Post summary
The post announces a deserialization vulnerability (CVE‑2026‑50517) in Microsoft 365 Copilot that permits authenticated attackers to run code over the network. No active exploitation or PoC is reported, but patching via updates is recommended.
#securityupdate #microsoft #定例外 CVE-2026-50517 「…するために、お客様が取るべきアクションはありません」 影響: リモートでコードが実行される 最大深刻度: 緊急 CVSS:3.1 9.9 / 8.6 悪用可能性 ・一般に公開: No ・悪用: No ・Exploitability assessment: 対象外 https://x.com/kawn2020/status/2081628226619895844
Post summary
An advisory for CVE-2026-50517 indicates a high‑severity remote code execution flaw with no currently known exploits and no required mitigation steps.
CVE-2026-50517 (CVSS 9.9) in M365 Copilot allows authorized attackers remote code execution via deserialization. Assess exposure if your org uses Copilot. via NVD Recent High CVSS #CyberSecurity #InfoSec #Vulnerability https://t.co/2xrQkdIEfU
Post summary
The tweet announces CVE‑2026‑50517, a high‑severity RCE risk in Microsoft 365 Copilot, without providing PoC, exploit code, or remediation details.
It is possible to see elevated activities targeting Microsoft Copilot (CVE-2026-50517) https://vuldb.com/vuln/382842/cti
Post summary
The post mentions possible heightened activity around CVE‑2026‑50517 for Microsoft Copilot but provides no concrete details on PoC, exploitation tactics, patches, or technical aspects.
🔒 #CyberSecurity CVE-2026-50517: M365 Copilot RCE via Deserialization — Defense and Hardening Gu… "Today, the NVD published CVE-2026-50517, assigning it a CVSS score of 9.9 (CRITICAL)." 🔗 https://securityarsenal.com/blog/cve-2026-50517-m365-copilot-rce-via-deserialization-defense-and-hardening-guide #CyberSecurity #ThreatIntel #cve202650517 #critical #cve
Post summary
The post announces the newly published CVE‑2026‑50517, providing its critical severity score and describing it as an RCE via deserialization, without indicating an exploit or patch.
🚨 M365 Copilot Deserialization RCE — CVSS 9.9 CVE-2026-50517: Authorized attackers can execute code via insecure deserialization. Service-side patch via Microsoft Security Update Guide. → http://threataft.com/articles/microsoft-m365-copilot-cve-2026-50517 #cybersecurity #infosec #Microsoft #Copilot #AI
Post summary
The tweet alerts about a high‑severity CVE‑2026‑50517 in Microsoft 365 Copilot that allows code execution via insecure deserialization and indicates a service‑side patch is available through Microsoft's Security Update Guide.
🚨 Microsoft 365 Copilot has a confirmed RCE vulnerability. AI workflows were meant to save time—not hand attackers the keyboard. Admins, check the advisory and patch now. https://windowsforum.com/threads/cve-2026-50517-microsoft-365-copilot-rce-confirmed.440229/?utm_source=x&utm_medium=social&utm_campaign=news_node84 #RemoteCodeExecution #CloudSecurity #Cve202650517 #MicrosoftM365Copilot https://t.co/mBxbm8MBMz
Post summary
A confirmed RCE in Microsoft 365 Copilot has been reported; admins are urged to review the advisory and apply patches immediately.
1 of 1 entries
| Part | Vendor | Product | Version | Target SW | Target HW |
|---|---|---|---|---|---|
| App | microsoft | 365_copilot | - | - | - |