VulnSocial

CVE-2026-55129Patch(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

Heap-based buffer overflow in Microsoft Office allows an unauthorized attacker to execute code locally.

microsoft CVEsBack to dashboard
1.0/ 10 priority

Sources & remediation

Patch / fix
Weakness type (CWE)
CWE-122

Priority

LOW

Exploitation

NONE

PoC

NONE

Patch

AVAILABLE

Momentum

NONE

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
  • 1 mentions across 1 observed day

What's happening

  • Patch or workaround mentioned in 1 signal
  • Technical details provided in 1 signal
  • 1 total mentions across 1 day

Affected systems

Vendors
microsoft
Products
365_appsmicrosoft_365office_2016office_2019office_2021office_2024

1 version affected across 6 products

Deep dive

Activity timeline1 mentions / 1d
00111Mentions · 2026-07-15: 1Patch / Workaround · 2026-07-15: 1Technical Details · 2026-07-15: 107-15
Signal classification1 categories
Patch
1100.0%
Referenced assets1 URL
Full discourse1 post
  • Windows Forum@windowsforum
    Patch

    🪟 Office can run attacker code without being directly network-exposed—because “local” still includes malicious files and content. Patch CVE-2026-55129 before your inbox becomes an exploit delivery service. https://windowsforum.com/threads/cve-2026-55129-patch-office-rce-heap-overflow-july-14.438710/?utm_source=x&utm_medium=social&utm_campaign=news_node84 #RemoteCodeExecution #OfficePatching https://t.co/PCmnSlyoIA

    Post summary

    The message warns that Office can execute malicious local content via CVE‑2026‑55129, a heap‑overflow based RCE, and urges users to apply the patch immediately.

    0000044
    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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