CVE-2026-55018Patch(microsoft / 365_apps)

LOWCVSS 7.8 · HIGH

Signal is active with 1 mentions in latest observed window

Immediate actions

  • Patch microsoft 365_apps systems immediately

Recommended action window: Monitor and triage in normal cycle

NVD description

Use after free in Microsoft Office allows an unauthorized attacker to execute code locally.

1.0/ 10 priority

Sources & remediation

Weakness type (CWE)
CWE-416

Priority

LOW

Exploitation

NONE

PoC

NONE

Patch

AVAILABLE

Momentum

STABLE

Are you affected?

If you run products in this scope, you should treat this CVE as relevant to your environment.

  • 365_apps
  • microsoft_365
  • office_2016
  • office_2019

Threat summary

  • Patch or workaround signal is available
  • 2 mentions across 2 observed days
  • Momentum state: stable

What's happening

  • Patch or workaround mentioned in 2 signals
  • Technical details provided in 2 signals
  • Peaked 1d ago at 1 mentions (2026-07-15); latest day: 1
  • 2 total mentions across 2 days

Affected systems

Vendors
Products
365_appsmicrosoft_365office_2016office_2019office_2021office_2024

1 version affected across 6 products

Deep dive

Activity timeline2 mentions / 2d
00111Mentions · 2026-07-15: 1Mentions · 2026-07-18: 1Patch / Workaround · 2026-07-15: 1Patch / Workaround · 2026-07-18: 1Technical Details · 2026-07-15: 1Technical Details · 2026-07-18: 107-1507-18
Signal classification1 categories
Patch
2100.0%
Referenced assets1 URL
Full discourse2 posts
  • DFIR Lab@DFIR_Lab
    Patch

    🚨 HIGH SEVERITY: CVE-2026-55018 (CVSS 7.8) Use-after-free in Microsoft Office enables local code execution by unauthorized attackers. User interaction required. Patch immediately. #CVE #Vulnerability #PatchNow #ThreatIntel #DFIR https://t.co/dblG6RYHd0

    Post summary

    High severity use‑after‑free vulnerability in Microsoft Office (CVE‑2026‑55018) that requires user interaction; immediate patching is recommended.

    0000047
    82 followersView on X
  • Windows Forum@windowsforum
    Patch

    🚨 Office users: KB5002887 patches a critical RCE triggered by malicious content. “Just don’t open weird files” remains a security strategy with a terrible success rate. https://windowsforum.com/threads/cve-2026-55018-patch-critical-office-rce-with-kb5002887.438667/?utm_source=x&utm_medium=social&utm_campaign=news_node84 #MicrosoftOffice #OfficeSecurity #PatchTuesday #Cve202655018 https://t.co/S0IyJYyCmQ

    Post summary

    The tweet announces that KB5002887 patches CVE‑2026‑55018, a critical Office Remote Code Execution vulnerability, and stresses the importance of applying the update.

    000008
    1.2K followersView on X
CPE platform detail13 entries

13 of 13 entries

PartVendorProductVersionTarget SWTarget HW
Appmicrosoft365_apps--x64
Appmicrosoft365_apps--x86
Appmicrosoftmicrosoft_365-macos-
Appmicrosoftoffice_2016--x64
Appmicrosoftoffice_2016--x86
Appmicrosoftoffice_2019--x64
Appmicrosoftoffice_2019--x86
Appmicrosoftoffice_2021--x64
Appmicrosoftoffice_2021--x86
Appmicrosoftoffice_2021-macos-
Appmicrosoftoffice_2024--x64
Appmicrosoftoffice_2024--x86
Appmicrosoftoffice_2024-macos-

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