Skip to main content
View

Attack ChainAIDerived

Hypothetical attack flow derived from CVE metadata – not a confirmed exploit chain

  1. Access
    Deliver crafted Word document via email/web
  2. Delivery
    Victim opens document in Office Word
  3. Exploit
    Trigger out-of-bounds read in file parser
  4. Execution
    Leak adjacent process memory
  5. Impact
    Exfiltrate disclosed information to attacker

Vulnerability Assessment

Weakness
CWE
ASVS 5.0
V15 - Secure Coding and Architecture Bounds checking, read limits
MITRE ATT&CK

1 technique across 1 tactic: Collection

The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up.

Exploitation Conditions

Exploitation requires the victim to open an attacker-crafted Word document in an affected Office/Word build (UI:R in the CVSS vector) - it is not a wormable, zero-click, or server-side flaw. No authentication or special privileges are needed on the target (PR:N), and default configurations are vulnerable, but the attack is limited by the need for user interaction and successful social engineering to deliver and open the malicious file. Impact is confined to disclosure of process memory (C:H, I:N, A:N); it does not by itself yield code execution or persistence.

Impact

This is a moderate-severity information disclosure flaw (CVSS 6.5) driven by an out-of-bounds read (CWE-125) in Microsoft Office Word. The CVSS vector CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N indicates network-reachable, low-complexity, unauthenticated exploitation but is gated by required user interaction (UI:R) - the victim must open a crafted document. Impact is confidentiality-only (C:H, I:N, A:N): the bug leaks memory contents, it does not grant code execution or data tampering. No EPSS score, KEV listing, or POC was provided in the input, so there is no public exploit identified at time of analysis and no evidence of active exploitation. The practical risk is real but secondary to RCE-class Office bugs: the UI:R requirement means it depends on social engineering, and the confidentiality-only impact (memory disclosure, potentially useful for ASLR bypass chained with other bugs) limits standalone severity. Note: AV:N is standard Microsoft convention for file-delivered Office attacks even though delivery is typically via email/download rather than a live network protocol - the 'network' label reflects remote delivery, not a listening service, so defenders should treat this as a document-borne threat.

Exploit ScenarioDerived

An attacker emails or hosts a specially crafted Word document and lures a victim into opening it. When Word parses the malformed structure, an out-of-bounds read exposes adjacent process memory, which is exfiltrated back to the attacker (e.g., via embedded remote content or a chained leak). No public exploit code was identified in the provided data, and success depends on the user opening the file.

This Month Plan within 30 days. Why: MEDIUM severity (CVSS 4.0-6.9).
Patch available 0.5% exploitation probability (EPSS)

Get an e-mail when this CVE is exploited, patched or re-scored. Free account.

Alert me

AnalysisAIv1 – Oct 15, 2026

An out-of-bounds read in Microsoft Word (CWE-125) lets remote, unauthenticated attackers disclose the contents of process memory when a victim opens a specially crafted document, with affected builds spanning Microsoft 365 Apps for Enterprise, Office 365 for Mac, Office LTSC 2021/2024, and Office LTSC for Mac 2021/2024. Exploitation requires the user to open the malicious file (UI:R) and deliver it successfully through social engineering, so it is not a zero-click or wormable flaw, and the impact is limited to information disclosure (C:H, I:N, A:N) without code execution or persistence. No public exploit code has been identified at time of analysis, and Microsoft has published a vendor patch through its update guide.

RemediationAI

Microsoft has released a fix through its normal update channels and the advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-108436 should be used to identify and deploy the specific patched builds for Microsoft 365 Apps for Enterprise, Office 365 for Mac, and Office LTSC 2021/2024 on Windows and macOS (patch status: patch available per vendor advisory; an exact fix version is not specified in the available data, so consult the MSRC page rather than assuming a version number). Where immediate patching is not possible, reduce exposure by opening untrusted documents in Windows Defender Application Guard for Office or Protected View, enforcing the Office Trust Center policy that blocks files originating from the internet, and using mail-gateway/Defender for Office attachment detonation to filter weaponized documents - noting that Application Guard and Protected View add friction and may break legitimate add-ins, macros, and cross-application workflows, and that pre-filtering cannot catch every crafted file. Because exploitation depends on a user opening a malicious document, user awareness training on unexpected attachments plus endpoint detection tuned to anomalous Word memory-read behavior are useful compensating controls, but none replace installing the vendor update.

Affected VersionsENISA

Microsoft Office 365 for Mac 1.0.0 <16.114.26101123
Microsoft 365 Apps for Enterprise 16.0.1 <https://aka.ms/OfficeSecurityReleases
Microsoft Office LTSC 2021 16.0.1 <16.0.14334.20974
Microsoft Office LTSC 2024 16.0.0 <16.0.17932.21056
Microsoft Office LTSC for Mac 2024 16.0.0 <16.114.26101123
Microsoft Office LTSC for Mac 2021 16.0.1 <16.114.26101123

Affected Packages

euvd microsoft_office_365_for_mac fix: 16.114.26101123
euvd microsoft_office_ltsc_2021 fix: 16.0.14334.20974
euvd microsoft_office_ltsc_2024 fix: 16.0.17932.21056
euvd microsoft_office_ltsc_for_mac_2021 fix: 16.114.26101123
euvd microsoft_office_ltsc_for_mac_2024 fix: 16.114.26101123

Source: OSV (Open Source Vulnerabilities)

Affects your stack

Affects 5 packages in euvd

Checking this CVE against your own stacks and servers is part of the Basic plan and up.

Technical ContextAI · show details

The root cause is an out-of-bounds read (CWE-125) in the code Word uses to parse and render document content, where the application reads past the end of an allocated buffer and can return adjacent heap memory to the attacker - for example, embedding leaked bytes into rendered output or otherwise exposing them. Per the assessed CVSS vector CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N, the attack is network-deliverable with low complexity, needs no authentication or privileges on the target (PR:N), but requires victim interaction (UI:R) to open the crafted file, and the sole security consequence is high confidentiality loss. The CPE data identifies the vulnerable surface as the shared Word parsing engine across Microsoft 365 Apps for Enterprise, Microsoft Office 365 for Mac, Office LTSC 2021, Office LTSC 2024, Office LTSC for Mac 2021, and Office LTSC for Mac 2024, which is consistent with a single memory-safety defect in a component common to these desktop builds.

Know when Microsoft 365 Apps For Enterprise gets its next vulnerability

  • Watch products and get an email when something new is published
  • Check this CVE against your own stack and servers
  • Exploit and PoC references, threat intelligence from 22 sources

No credit card · 7-day full trial

Severity by source

Vendor (microsoft) PRIMARY 6.5 MEDIUM
AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
vuln.today AI 6.5 MEDIUM

File is delivered remotely (AV:N) but requires the user to open it (UI:R); no privileges needed (PR:N); out-of-bounds read discloses memory so C:H, I:N, A:N.

3.1 AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
4.0 AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N

Primary rating from Vendor (microsoft).

CVSS VectorVendor: microsoft

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
Required
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
None

DescriptionCVE.org

Out-of-bounds read in Microsoft Office Word allows an unauthorized attacker to disclose information over a network.

Threat Intelligence Overview

EPSS Score
0.5%
Top 58% exploitable
Prevalence
Ubiquitous
Microsoft Office/Word and Microsoft 365 Apps deployed across most enterprise environments
Vendor Status
Publicly Disclosed:No
Exploited:No
Latest Software Release:Exploitation Less Likely
Data Quality
5 sources
Confidence: Medium

How this decision was reached

The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.

SignalValue
Severity MEDIUM
CISA KEV No
Public POC No
EPSS 0.5%
Patch available Yes
Active threat No
Deciding rule
MEDIUM severity (CVSS 4.0-6.9)
What every action level means
Emergency Immediate action required. Criteria: CRITICAL + in CISA KEV (actively exploited) without patch, OR CRITICAL + EPSS > 30% without patch, OR CRITICAL + active threat signals without patch.
Act Now Prioritize within 24-48h. Criteria: in KEV with patch available, OR CRITICAL + public POC, OR HIGH + EPSS > 10%, OR CRITICAL + active threat, OR any CRITICAL severity.
This Week Schedule remediation this week. Criteria: HIGH severity (CVSS 7.0-8.9). Patch within normal change window.
This Month Plan within 30 days. Criteria: MEDIUM severity (CVSS 4.0-6.9), lower exploitation probability. Include in regular patch cycle.
Monitor Track and reassess. Criteria: LOW severity (CVSS 0.1-3.9), minimal exploitation risk. No immediate action needed.

SSVC AssessmentENISA

SSVC Decision· derived
Scheduled
Exploitation
None
System Exposure· derived
Open
Automatable
No
Human Impact· derived
Medium
Technical Impact
Partial

Priority Score

33
Low Medium High Critical
KEV: 0
EPSS: +1
CVSS: +32
PoC: 0
Weaponized: 0
Threat intel: 0
Gov advisory: 0

Attack Technique

A buffer overflow occurs when a program writes more data to a memory buffer than it was allocated to hold, causing the excess data to spill into adjacent memory regions.

Information disclosure occurs when an application unintentionally exposes sensitive data that aids attackers in reconnaissance or directly compromises security.

CVE-2026-55033 HIGH
7.8 Jul 14

Local code execution in Microsoft Word (and Office/SharePoint components that render Word content) stems from an integer

CVE-2026-55038 HIGH
7.8 Jul 14

Arbitrary code execution in Microsoft Office Word (and the broader Office/365/SharePoint family) arises from a stack-bas

CVE-2026-55132 HIGH
7.8 Jul 14

Local code execution in Microsoft Word (part of Microsoft 365 Apps, Office 2019, Office LTSC 2021/2024, and Office for M

CVE-2026-55120 HIGH
7.8 Jul 14

Arbitrary code execution in Microsoft PowerPoint (and the broader Microsoft Office/365 suite on Windows and macOS) arise

CVE-2026-55123 HIGH
7.8 Jul 14

Local code execution in Microsoft Office PowerPoint (including Microsoft 365 Apps, Office 2019, Office LTSC 2021/2024, a

CVE-2026-55043 HIGH
7.8 Jul 14

Local code execution in Microsoft Office PowerPoint (CWE-122 heap-based buffer overflow) lets an unauthorized attacker r

CVE-2026-55127 HIGH
7.8 Jul 14

Local code execution in Microsoft Word (and the wider Microsoft Office / Microsoft 365 Apps family) lets an unauthorized

CVE-2026-55130 HIGH
7.8 Jul 14

Local code execution in Microsoft Word (Office 2016/2019, Microsoft 365 Apps, Office LTSC 2021/2024) arises from a heap-

CVE-2026-55128 HIGH
7.8 Jul 14

Local code execution in Microsoft Office Word (CWE-416 use-after-free) allows an unauthorized attacker to run arbitrary

CVE-2026-55134 HIGH
7.8 Jul 14

Local code execution in Microsoft Office Word (Microsoft 365 Apps, Office 2019/LTSC 2021/2024, Word 2016, and the macOS

CVE-2026-55055 HIGH
7.8 Jul 14

Local code execution in Microsoft Office Word (via a stack-based buffer overflow, CWE-121) lets an attacker run arbitrar

CVE-2026-55032 HIGH
7.8 Jul 14

Local code execution in Microsoft Office Word (across Microsoft 365 Apps, Office 2019/LTSC 2021/2024, Office for Mac, an

This site uses cookies essential for authentication and security. No tracking or analytics cookies are used. Privacy Policy