CVE-2026-70337: Microsoft PowerShell Remote Code Execution Vulnerability
CVE-2026-70337 is a remote code execution vulnerability in Microsoft PowerShell, rated Important by Microsoft, with a CVSS 3.1 base score of 8.8 (High). An attacker can exploit it remotely over the network, without any privileges and only if a user takes an action. Microsoft has not reported exploitation in the wild and rates exploitation as less likely. The EPSS model estimates a 0.94% probability of exploitation activity in the next 30 days, higher than 61% of all scored vulnerabilities. Microsoft released the fix on 11 August 2026 in the August 2026 Patch Tuesday. It affects 3 products in 1 product family (Developer Tools).
Key facts
- CVE ID
- CVE-2026-70337
- Severity
- High CVSS 8.8
- Microsoft severity
- Important
- Impact
- Remote Code Execution
- Exploited in the wild
- No
- Publicly disclosed
- No
- Exploitation likelihood
- Less Likely
- Weakness
- CWE-23
- EPSS
- 0.94% (percentile 61%)
- CISA KEV
- Not listed
- Released
- Last updated
- Patch Tuesday
- August 2026 Patch Tuesday
- Product families
- Developer Tools
CVSS score and vector
Microsoft scores CVE-2026-70337 at 8.8 (temporal 7.7) using CVSS 3.1. Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
| Metric | Value |
|---|---|
| Attack vector | Network |
| Attack complexity | Low |
| Privileges required | None |
| User interaction | Required |
| Scope | Unchanged |
| Confidentiality impact | High |
| Integrity impact | High |
| Availability impact | High |
| Exploit code maturity | Unproven |
| Remediation level | Official fix |
| Report confidence | Confirmed |
Description
Relative path traversal in Microsoft PowerShell Core allows an unauthorized attacker to execute code over a network.
Frequently asked questions (Microsoft)
How could an attacker exploit this vulnerability?
An attacker could host a malicious server and convince a user to connect to it from an affected client. When the client processes the server's response, the attacker could execute code on the client system. User interaction is required.
Affected products (3)
Developer Tools
| Product | Security update | Type | Fixed build | Restart |
|---|---|---|---|---|
| PowerShell 7.5 | Security update | Security Update | 7.5.10.0 | Maybe |
| PowerShell 7.4 | Security update | Security Update | 7.4.19.0 | Maybe |
| PowerShell 7.6 | Security update | Security Update | 7.6.5 | Maybe |
NIST NVD data
- NVD status
- Analyzed
- NVD CVSS
- 8.8 (HIGH)
- NVD weakness
- CWE-23
- Published to NVD
- NVD last modified
Affected configurations (CPE)
| Product | Vulnerable versions |
|---|---|
| powershell | from 7.4, before 7.4.19.0 |
| powershell | from 7.5, before 7.5.10.0 |
| powershell | from 7.6, before 7.6.5 |
References
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-70337 (Vendor Advisory)
Acknowledgments
- 0hmz
- 71C4
- Anindya Roy
- Anonymous
- Ayato Shitomi
- Charlie Vogt
- f7d8c52bec79e42795cf15888b85cbad
- Hasan Flayyih Abdullah
- l8BL with ENKI WhiteHat
- Manan Patel
- Moath Aloufi
- Mohit_Negi with Bugcrowd
- NavSec with NavSec
- xboy
Revision history
| Version | Date | Description |
|---|---|---|
| 1.0 | Information published. | |
| 2.0 | The security updates for Powershell have been updated. | |
| 2.1 | Acknowledgement Updated | |
| 2.2 | Acknowledgement Updated | |
| 2.3 | Acknowledgement Updated | |
| 2.4 | Updated an acknowledgement. This is an informational change only. |