Microsoft Outlook - Remote Code Execution (RCE)

Exploit Author: nu11secur1ty Analysis Author: www.bubbleslearn.ir Category: Remote Language: Python Published Date: 2025-07-08

# Titles: Microsoft Outlook - Remote Code Execution (RCE)
# Author: nu11secur1ty
# Date: 07/06/2025
# Vendor: Microsoft
# Software: https://www.microsoft.com/en-us/microsoft-365/outlook/log-in
# Reference:
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-47176 >
https://www.cloudflare.com/learning/security/what-is-remote-code-execution/
# CVE-2025-47176

## Description
This proof-of-concept (PoC) demonstrates the CVE-2025-47176 vulnerability
simulation. It injects a crafted mail item into Outlook containing a
malicious sync path that triggers an action during scanning.

**IMPORTANT:**
This PoC simulates the vulnerable Outlook path parsing and triggers a
**system restart** when the malicious path is detected.

---
## Additional Testing with malicious.prf

You can also test this PoC by importing a crafted Outlook Profile File
(`malicious.prf`):

1. Place `malicious.prf` in the same folder as `PoC.py`.
2. Run Outlook with the import command:

   ```powershell
   & "C:\Program Files\Microsoft Office\root\Office16\OUTLOOK.EXE"
/importprf malicious.prf


## Usage

1. Ensure you have Outlook installed and configured on your Windows machine.
2. Run the PoC script with Python 3.x (requires `pywin32` package):
   ```powershell
   pip install pywin32
   python PoC.py
   ```
3. The script will:
   - Inject a mail item with the malicious sync path.
   - Wait 10 seconds for Outlook to process the mail.
   - Scan Inbox and Drafts folders.
   - Upon detection, normalize the path and trigger a system restart
(`shutdown /r /t 5`).

---

## Warning

- This script **will restart your computer** after 5 seconds once the
payload is triggered.
- Save all work before running.
- Test only in a controlled or virtualized environment.
- Do **NOT** run on production or important systems.

---

## Files

- `PoC.py` - The Python proof-of-concept script.
- `README.md` - This file.

---

## License

This PoC is provided for educational and research purposes only.

Use responsibly and ethically.


# Video:
[href](https://www.youtube.com/watch?v=nac3kUe_d1c)

# Source:
[href](
https://github.com/nu11secur1ty/CVE-mitre/tree/main/2025/CVE-2025-47176)

# Buy me a coffee if you are not ashamed:
[href](https://www.paypal.com/donate/?hosted_button_id=ZPQZT5XMC5RFY)

# Time spent:
03:35:00


-- 
System Administrator - Infrastructure Engineer
Penetration Testing Engineer
Exploit developer at https://packetstormsecurity.com/
https://cve.mitre.org/index.html
https://cxsecurity.com/ and https://www.exploit-db.com/
0day Exploit DataBase https://0day.today/
home page: https://www.nu11secur1ty.com/
hiPEnIMR0v7QCo/+SEH9gBclAAYWGnPoBIQ75sCj60E=
                          nu11secur1ty <http://nu11secur1ty.com/>


На нд, 6.07.2025 г. в 10:34 nu11 secur1ty <nu11secur1typentest@gmail.com>
написа:

> # Titles: Microsoft Outlook Remote Code Execution Vulnerability - ACE
> # Author: nu11secur1ty
> # Date: 07/06/2025
> # Vendor: Microsoft
> # Software: https://www.microsoft.com/en-us/microsoft-365/outlook/log-in
> # Reference:
> https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-47176 >
> https://www.cloudflare.com/learning/security/what-is-remote-code-execution/
> # CVE-2025-47176
>
> ## Description
> This proof-of-concept (PoC) demonstrates the CVE-2025-47176 vulnerability
> simulation. It injects a crafted mail item into Outlook containing a
> malicious sync path that triggers an action during scanning.
>
> **IMPORTANT:**
> This PoC simulates the vulnerable Outlook path parsing and triggers a
> **system restart** when the malicious path is detected.
>
> ---
> ## Additional Testing with malicious.prf
>
> You can also test this PoC by importing a crafted Outlook Profile File
> (`malicious.prf`):
>
> 1. Place `malicious.prf` in the same folder as `PoC.py`.
> 2. Run Outlook with the import command:
>
>    ```powershell
>    & "C:\Program Files\Microsoft Office\root\Office16\OUTLOOK.EXE"
> /importprf malicious.prf
>
>
> ## Usage
>
> 1. Ensure you have Outlook installed and configured on your Windows
> machine.
> 2. Run the PoC script with Python 3.x (requires `pywin32` package):
>    ```powershell
>    pip install pywin32
>    python PoC.py
>    ```
> 3. The script will:
>    - Inject a mail item with the malicious sync path.
>    - Wait 10 seconds for Outlook to process the mail.
>    - Scan Inbox and Drafts folders.
>    - Upon detection, normalize the path and trigger a system restart
> (`shutdown /r /t 5`).
>
> ---
>
> ## Warning
>
> - This script **will restart your computer** after 5 seconds once the
> payload is triggered.
> - Save all work before running.
> - Test only in a controlled or virtualized environment.
> - Do **NOT** run on production or important systems.
>
> ---
>
> ## Files
>
> - `PoC.py` - The Python proof-of-concept script.
> - `README.md` - This file.
>
> ---
>
> ## License
>
> This PoC is provided for educational and research purposes only.
>
> Use responsibly and ethically.
>
>
> # Reproduce:
> [href](https://www.youtube.com/watch?v=yOra0pm8CHg)
>
> # Source:
> [href](
> https://github.com/nu11secur1ty/CVE-mitre/tree/main/2025/CVE-2025-47176)
>
> # Buy me a coffee if you are not ashamed:
> [href](https://www.paypal.com/donate/?hosted_button_id=ZPQZT5XMC5RFY)
>
> # Time spent:
> 03:35:00
>
>
> --
> System Administrator - Infrastructure Engineer
> Penetration Testing Engineer
> Exploit developer at https://packetstormsecurity.com/
> https://cve.mitre.org/index.html
> https://cxsecurity.com/ and https://www.exploit-db.com/
> 0day Exploit DataBase https://0day.today/
> home page: https://www.nu11secur1ty.com/
> hiPEnIMR0v7QCo/+SEH9gBclAAYWGnPoBIQ75sCj60E=
>                           nu11secur1ty <http://nu11secur1ty.com/>
>
> На нд, 6.07.2025 г. в 9:53 nu11 secur1ty <nu11secur1typentest@gmail.com>
> написа:
>
>> # Titles: Microsoft Outlook Remote Code Execution Vulnerability - ACE
>> # Author: nu11secur1ty
>> # Date: 07/06/2025
>> # Vendor: Microsoft
>> # Software: https://www.microsoft.com/en-us/microsoft-365/outlook/log-in
>> # Reference:
>> https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-47176 >
>> https://www.cloudflare.com/learning/security/what-is-remote-code-execution/
>> # CVE-2025-47176
>>
>> ## Description
>> This proof-of-concept (PoC) demonstrates the CVE-2025-47176 vulnerability
>> simulation. It injects a crafted mail item into Outlook containing a
>> malicious sync path that triggers an action during scanning.
>>
>> **IMPORTANT:**
>> This PoC simulates the vulnerable Outlook path parsing and triggers a
>> **system restart** when the malicious path is detected.
>>
>> ---
>> ## Additional Testing with malicious.prf
>>
>> You can also test this PoC by importing a crafted Outlook Profile File
>> (`malicious.prf`):
>>
>> 1. Place `malicious.prf` in the same folder as `PoC.py`.
>> 2. Run Outlook with the import command:
>>
>>    ```powershell
>>    & "C:\Program Files\Microsoft Office\root\Office16\OUTLOOK.EXE"
>> /importprf malicious.prf
>>
>>
>> ## Usage
>>
>> 1. Ensure you have Outlook installed and configured on your Windows
>> machine.
>> 2. Run the PoC script with Python 3.x (requires `pywin32` package):
>>    ```powershell
>>    pip install pywin32
>>    python PoC.py
>>    ```
>> 3. The script will:
>>    - Inject a mail item with the malicious sync path.
>>    - Wait 10 seconds for Outlook to process the mail.
>>    - Scan Inbox and Drafts folders.
>>    - Upon detection, normalize the path and trigger a system restart
>> (`shutdown /r /t 5`).
>>
>> ---
>>
>> ## Warning
>>
>> - This script **will restart your computer** after 5 seconds once the
>> payload is triggered.
>> - Save all work before running.
>> - Test only in a controlled or virtualized environment.
>> - Do **NOT** run on production or important systems.
>>
>> ---
>>
>> ## Files
>>
>> - `PoC.py` - The Python proof-of-concept script.
>> - `README.md` - This file.
>>
>> ---
>>
>> ## License
>>
>> This PoC is provided for educational and research purposes only.
>>
>> Use responsibly and ethically.
>>
>>
>> # Reproduce:
>> [href](https://www.youtube.com/watch?v=yOra0pm8CHg)
>>
>> # Buy me a coffee if you are not ashamed:
>> [href](https://www.paypal.com/donate/?hosted_button_id=ZPQZT5XMC5RFY)
>>
>> # Time spent:
>> 03:35:00
>>
>>
>> --
>> System Administrator - Infrastructure Engineer
>> Penetration Testing Engineer
>> Exploit developer at https://packetstormsecurity.com/
>> https://cve.mitre.org/index.html
>> https://cxsecurity.com/ and https://www.exploit-db.com/
>> 0day Exploit DataBase https://0day.today/
>> home page: https://www.nu11secur1ty.com/
>> hiPEnIMR0v7QCo/+SEH9gBclAAYWGnPoBIQ75sCj60E=
>>                           nu11secur1ty <http://nu11secur1ty.com/>
>>
>> --
>>
>> System Administrator - Infrastructure Engineer
>> Penetration Testing Engineer
>> Exploit developer at https://packetstorm.news/
>> https://cve.mitre.org/index.html
>> https://cxsecurity.com/ and https://www.exploit-db.com/
>> 0day Exploit DataBase https://0day.today/
>> home page: https://www.nu11secur1ty.com/
>> hiPEnIMR0v7QCo/+SEH9gBclAAYWGnPoBIQ75sCj60E=
>>                           nu11secur1ty <http://nu11secur1ty.com/>
>>
>
>
> --
>
> System Administrator - Infrastructure Engineer
> Penetration Testing Engineer
> Exploit developer at https://packetstorm.news/
> https://cve.mitre.org/index.html
> https://cxsecurity.com/ and https://www.exploit-db.com/
> 0day Exploit DataBase https://0day.today/
> home page: https://www.nu11secur1ty.com/
> hiPEnIMR0v7QCo/+SEH9gBclAAYWGnPoBIQ75sCj60E=
>                           nu11secur1ty <http://nu11secur1ty.com/>
>


-- 

System Administrator - Infrastructure Engineer
Penetration Testing Engineer
Exploit developer at https://packetstorm.news/
https://cve.mitre.org/index.html
https://cxsecurity.com/ and https://www.exploit-db.com/
0day Exploit DataBase https://0day.today/
home page: https://www.nu11secur1ty.com/
hiPEnIMR0v7QCo/+SEH9gBclAAYWGnPoBIQ75sCj60E=
                          nu11secur1ty <http://nu11secur1ty.com/>

Microsoft Outlook — Remote Code Execution (CVE-2025-47176)

This article summarizes the CVE-2025-47176 remote code execution (RCE) vulnerability affecting Microsoft Outlook, explains likely attack scenarios, and provides defensive guidance for detection, mitigation, and incident response. The goal is to give security teams and administrators practical, non-actionable guidance to reduce risk and respond effectively.

Vulnerability overview

CVE-2025-47176 is a vulnerability in Microsoft Outlook's handling of certain sync/path values embedded in mail items or profiles. When Outlook processes a crafted mail item or profile configuration, the path-parsing logic can be abused to trigger unintended behavior that could lead to remote code execution. Public activity around this CVE included a demonstration that simulated the vulnerable behavior; researchers noted the demonstration caused an immediate system action (a restart) when a malicious path was detected.

Why this matters

Remote code execution in an email client is high-severity: an attacker who can cause execution within the user’s context may achieve persistence, lateral movement, or data theft.
Email clients run with user privileges and often interact with other system components (file system, shell, sync engines), increasing the attack surface.
Automated processing of mail items and profile imports (for example via client sync, server-side rules, or administrative profile deployment) can expand the window of exposure beyond just the user actively opening an email.

Quick facts (summary)

Item	Detail
CVE	CVE-2025-47176
Vendor advisory	Microsoft Security Response Center (MSRC)
Discovery / public disclosure	Reported publicly in July 2025; PoC material was published by independent researchers (exercise caution — PoCs may be disruptive)
Risk	High — potential for remote code execution

Typical attack scenarios (high-level)

An attacker crafts an email or profile configuration containing specially formed path/sync metadata and sends it to a target user. Outlook’s automatic processing (preview, synchronization, or profile import) triggers the vulnerable code path.
An attacker compromises an internal mail relay or collaboration system and injects malicious items into mailboxes that are then processed by clients or sync agents.
Aggregate campaigns that exploit this bug could be used as an initial access vector by phishing or by weaponizing malicious profile files distributed through other channels (malicious configuration imports), although admins should treat any such files as untrusted.

Detection and monitoring (defensive guidance)

Detection is primarily behavioral and telemetry-driven. Instrument EDR/AV and SIEM to look for anomalous activity originating from Outlook processes, unusual profile imports, and unexpected downstream process creation.

Monitor for Outlook (OUTLOOK.EXE) initiating child processes that are not typical for your environment (cmd.exe, powershell.exe, wscript.exe, scripts launching installers, or other system utilities). Sudden process trees where Outlook spawns command interpreters are suspicious.
Watch for changes to profile or sync configurations arriving from unusual sources (new or unexpected PRF/profile import activities, profile-related registry or file writes tied to Outlook).
Correlate email receipt logs from mail gateways with endpoint telemetry — identify emails with uncommon headers, attachments, or embedded configuration data processed around the time of suspicious endpoint events.
Leverage Office telemetry and Microsoft 365 Defender signals to detect Office clients processing suspicious content.

# Defensive PowerShell example (non-destructive) — query installed Outlook/Office versions from registry
Get-ItemProperty -Path 'HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\*' |
  Where-Object { $_.DisplayName -like '*Outlook*' -or $_.DisplayName -like '*Microsoft 365*' } |
  Select-Object DisplayName, DisplayVersion, Publisher

Explanation: This read-only PowerShell snippet enumerates registry uninstall keys to discover installed Office/Outlook products and their versions. Use this to build an inventory and prioritize patching for hosts that run Outlook.

Example SIEM rule concept (platform-agnostic): monitor events where the initiating process is an Outlook executable and the child process is a shell or scripting engine, and then alert for rare or previously unseen command-line parameters. Implement rate-limiting and whitelisting for known benign automation to reduce false positives.

Mitigation and hardening (recommended actions)

Patch immediately: apply vendor updates or the security update from Microsoft as directed in the MSRC advisory. Patching is the primary and most effective mitigation.
Reduce exposure: disable unnecessary automatic content rendering in Outlook (such as preview panes for untrusted mail) and block external content retrieval where possible.
Harden profile import and provisioning: limit the ability to import mailbox profiles or configuration files to trusted administrators; audit and control any automated provisioning tools.
Principle of least privilege: ensure users do not run with unnecessary elevated privileges and that service accounts have narrow scopes.
Email gateway controls: enable inbound attachment scanning, content disarm and reconstruction, and filter or quarantine messages containing unusual profile/configuration attachments or uncommon metadata patterns.
Endpoint security: ensure EDR/AV agents are up to date and configured to block or alert on suspicious process creation patterns originating from Outlook.

Incident response and remediation

If you detect suspected exploitation, isolate the impacted endpoint(s) from the network to prevent lateral movement and preserve forensic evidence.
Collect volatile and persistent artifacts (process trees, Office telemetry, mail headers, associated attachments, registry changes) and forward to your SOC or forensic team for analysis.
Reset credentials where lateral or credential theft is suspected and consider multifactor re-enrollment for affected accounts.
Apply the security update across affected systems, then validate that remediation succeeded before returning systems to normal operations.
Communicate with users: notify potentially impacted users to be wary of follow-up phishing and to report any unusual prompts or activity.

Responsible disclosure and public PoCs

Public PoCs and demonstrations for CVE-2025-47176 have been published by third-party researchers. Note that published PoCs may be disruptive (for example, simulated restarts or other system actions) and could be weaponized. Security teams should not run untrusted PoCs on production systems. Instead, use vendor-supplied guidance, test patches in isolated lab environments, and rely on trusted security vendors for defensive signatures.

Refer to vendor advisories and authoritative resources for official mitigations and patch availability:

Expert takeaways

Treat email clients as high-value targets: they interface with many systems and are commonly abused in initial-access campaigns.
Patching remains the fastest and most reliable risk reducer. Maintain an accurate inventory and apply critical updates in a timely manner.
Combine preventive controls (email gateway filtering, content rendering restrictions) with detection telemetry (EDR, SIEM) to create layered defenses.
When PoCs are public, prioritize defensive testing in isolated labs and use vendor guidance rather than running untrusted code on production systems.