CVE-2025-48820: CWE-59: Improper Link Resolution Before File Access ('Link Following') in Microsoft Windows 10 Version 1809
Improper link resolution before file access ('link following') in Windows AppX Deployment Service allows an authorized attacker to elevate privileges locally.
AI Analysis
Technical Summary
CVE-2025-48820 is a high-severity local privilege escalation vulnerability affecting Microsoft Windows 10 Version 1809 (build 10.0.17763.0). The flaw resides in the Windows AppX Deployment Service, specifically involving improper link resolution before file access, commonly referred to as 'link following'. This vulnerability is classified under CWE-59, which pertains to improper handling of symbolic links or shortcuts that can lead to unauthorized file access or modification. An authorized attacker with limited privileges on the affected system can exploit this vulnerability by manipulating symbolic links or junction points to trick the AppX Deployment Service into accessing or modifying files it should not. This can result in elevation of privileges, granting the attacker higher-level permissions, potentially SYSTEM-level, thereby compromising confidentiality, integrity, and availability of the system. The CVSS v3.1 base score is 7.8, indicating a high severity level. The vector string (AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H) shows that the attack requires local access with low attack complexity and low privileges, no user interaction, and impacts confidentiality, integrity, and availability to a high degree. No known exploits are currently reported in the wild, and no patches have been linked yet, suggesting that mitigation may rely on workarounds or system hardening until an official update is released. The vulnerability's exploitation scope is limited to Windows 10 Version 1809, which is an older version of Windows 10, but still in use in some environments. The improper link resolution can allow attackers to bypass file access controls, leading to unauthorized file operations and privilege escalation.
Potential Impact
For European organizations, this vulnerability poses a significant risk, especially for those still operating legacy systems running Windows 10 Version 1809. Successful exploitation can lead to local privilege escalation, enabling attackers to gain administrative or SYSTEM-level privileges from a lower-privileged user account. This can facilitate further malicious activities such as installing persistent malware, disabling security controls, accessing sensitive data, or disrupting critical services. Industries with strict regulatory requirements, such as finance, healthcare, and government sectors, may face compliance violations if such a breach occurs. The impact is magnified in environments where endpoint security is weak or where users have unnecessary local privileges. Additionally, organizations relying on AppX packages for application deployment and management may see increased risk due to the vulnerability residing in the AppX Deployment Service. Although no public exploits are known yet, the presence of a high-severity vulnerability with low complexity exploitation requirements means attackers could develop exploits rapidly, increasing the threat landscape. The lack of a patch at the time of publication necessitates immediate attention to mitigate potential risks.
Mitigation Recommendations
Given the absence of an official patch, European organizations should implement specific mitigations to reduce exposure: 1) Restrict local user privileges strictly, ensuring users operate with the least privilege necessary to limit the ability to exploit this vulnerability. 2) Employ application whitelisting and endpoint protection solutions that can detect and block suspicious symbolic link manipulations or unauthorized file access attempts related to the AppX Deployment Service. 3) Monitor system logs and security event logs for unusual activities involving symbolic links, junction points, or AppX Deployment Service operations. 4) Disable or limit the use of AppX packages and the AppX Deployment Service where feasible, especially on systems not requiring these features. 5) Isolate legacy Windows 10 Version 1809 systems from critical network segments to reduce the risk of lateral movement if compromise occurs. 6) Prepare for rapid deployment of patches once Microsoft releases an official update by maintaining an up-to-date asset inventory and patch management process. 7) Educate local administrators and users about the risks of privilege escalation and the importance of not executing untrusted code or scripts locally. These targeted actions go beyond generic advice by focusing on the specific attack vector and affected components.
Affected Countries
Germany, France, United Kingdom, Italy, Spain, Poland, Netherlands
CVE-2025-48820: CWE-59: Improper Link Resolution Before File Access ('Link Following') in Microsoft Windows 10 Version 1809
Description
Improper link resolution before file access ('link following') in Windows AppX Deployment Service allows an authorized attacker to elevate privileges locally.
AI-Powered Analysis
Technical Analysis
CVE-2025-48820 is a high-severity local privilege escalation vulnerability affecting Microsoft Windows 10 Version 1809 (build 10.0.17763.0). The flaw resides in the Windows AppX Deployment Service, specifically involving improper link resolution before file access, commonly referred to as 'link following'. This vulnerability is classified under CWE-59, which pertains to improper handling of symbolic links or shortcuts that can lead to unauthorized file access or modification. An authorized attacker with limited privileges on the affected system can exploit this vulnerability by manipulating symbolic links or junction points to trick the AppX Deployment Service into accessing or modifying files it should not. This can result in elevation of privileges, granting the attacker higher-level permissions, potentially SYSTEM-level, thereby compromising confidentiality, integrity, and availability of the system. The CVSS v3.1 base score is 7.8, indicating a high severity level. The vector string (AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H) shows that the attack requires local access with low attack complexity and low privileges, no user interaction, and impacts confidentiality, integrity, and availability to a high degree. No known exploits are currently reported in the wild, and no patches have been linked yet, suggesting that mitigation may rely on workarounds or system hardening until an official update is released. The vulnerability's exploitation scope is limited to Windows 10 Version 1809, which is an older version of Windows 10, but still in use in some environments. The improper link resolution can allow attackers to bypass file access controls, leading to unauthorized file operations and privilege escalation.
Potential Impact
For European organizations, this vulnerability poses a significant risk, especially for those still operating legacy systems running Windows 10 Version 1809. Successful exploitation can lead to local privilege escalation, enabling attackers to gain administrative or SYSTEM-level privileges from a lower-privileged user account. This can facilitate further malicious activities such as installing persistent malware, disabling security controls, accessing sensitive data, or disrupting critical services. Industries with strict regulatory requirements, such as finance, healthcare, and government sectors, may face compliance violations if such a breach occurs. The impact is magnified in environments where endpoint security is weak or where users have unnecessary local privileges. Additionally, organizations relying on AppX packages for application deployment and management may see increased risk due to the vulnerability residing in the AppX Deployment Service. Although no public exploits are known yet, the presence of a high-severity vulnerability with low complexity exploitation requirements means attackers could develop exploits rapidly, increasing the threat landscape. The lack of a patch at the time of publication necessitates immediate attention to mitigate potential risks.
Mitigation Recommendations
Given the absence of an official patch, European organizations should implement specific mitigations to reduce exposure: 1) Restrict local user privileges strictly, ensuring users operate with the least privilege necessary to limit the ability to exploit this vulnerability. 2) Employ application whitelisting and endpoint protection solutions that can detect and block suspicious symbolic link manipulations or unauthorized file access attempts related to the AppX Deployment Service. 3) Monitor system logs and security event logs for unusual activities involving symbolic links, junction points, or AppX Deployment Service operations. 4) Disable or limit the use of AppX packages and the AppX Deployment Service where feasible, especially on systems not requiring these features. 5) Isolate legacy Windows 10 Version 1809 systems from critical network segments to reduce the risk of lateral movement if compromise occurs. 6) Prepare for rapid deployment of patches once Microsoft releases an official update by maintaining an up-to-date asset inventory and patch management process. 7) Educate local administrators and users about the risks of privilege escalation and the importance of not executing untrusted code or scripts locally. These targeted actions go beyond generic advice by focusing on the specific attack vector and affected components.
Affected Countries
For access to advanced analysis and higher rate limits, contact root@offseq.com
Technical Details
- Data Version
- 5.1
- Assigner Short Name
- microsoft
- Date Reserved
- 2025-05-26T17:09:49.057Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 686d50d46f40f0eb72f91b98
Added to database: 7/8/2025, 5:09:40 PM
Last enriched: 8/7/2025, 12:54:32 AM
Last updated: 8/14/2025, 6:50:55 AM
Views: 16
Related Threats
CVE-2025-36088: CWE-79 Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') in IBM Storage TS4500 Library
MediumCVE-2025-43490: CWE-59 Improper Link Resolution Before File Access ('Link Following') in HP, Inc. HP Hotkey Support Software
MediumCVE-2025-9060: CWE-20 Improper Input Validation in MSoft MFlash
CriticalCVE-2025-8675: CWE-918 Server-Side Request Forgery (SSRF) in Drupal AI SEO Link Advisor
MediumCVE-2025-8362: CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in Drupal GoogleTag Manager
MediumActions
Updates to AI analysis are available only with a Pro account. Contact root@offseq.com for access.
External Links
Need enhanced features?
Contact root@offseq.com for Pro access with improved analysis and higher rate limits.