Know every vulnerabilitybefore it knows you.
DevGuard continuously monitors your dependencies and alerts you when CVEs like this one affect your stack — with real-time threat intelligence built for developers.
GHSA-g4v6-69p6-q3p4
No affected components available
Summary
Burn uses an unprotected C:\Windows\Temp directory to copy binaries and run them from there. This directory is not entirely protected against low privilege users.
Details
When a bundle runs as SYSTEM user, Burn uses GetTempPathW which points to an insecure directory C:\Windows\Temp to drop and load multiple binaries. Standard users can hijack the binary before it's loaded in the application resulting in elevation of privileges.
icacls c:\windows\temp
BUILTIN\Users:(CI)(S,WD,AD,X)
BUILTIN\Administrators:(F)
BUILTIN\Administrators:(OI)(CI)(IO)(F)
NT AUTHORITY\SYSTEM:(F)
NT AUTHORITY\SYSTEM:(OI)(CI)(IO)(F)
CREATOR OWNER:(OI)(CI)(IO)(F)
Built in users(non-administrators) have special permissions to this folder and can create files and write to this directory. While they do not have explicit read permissions, there is a way they can monitor the changes to this directory using ReadDirectoryChangesW API and thus figure out randomized folder names created inside this directory as wel
PoC
PoC works against the against visual studio enterprise with update 3 installer
Reproduction steps
As a standard user, run the poc. Mount the iso and run visual studio installer as local system account. The PoC should hijack the the binaries dropped by vs installer and a child process "notepad.exe" will be running.
Impact
This is an Elevation of Privilege Vulnerability where a low privileged user can hijack binaries in an unprotected path C:\Windows\Temp to elevate to the SYSTEM user privileges.
The vulnerability requires local access to the device to be exploited. It is easy for an attacker to exploit this vulnerability. An attacker needs basic access or low-level privileges. The attacker needs the user to perform some action, like clicking a link. The impact is confined to the system where the vulnerability exists. There is a high impact on the confidentiality of the information. There is a high impact on the integrity of the data. There is a high impact on the availability of the system.
Exploitation attempts have been detected. Elevated vigilance and prompt remediation are advised.
Probability that this vulnerability will be exploited in the wild within the next 30 days.
We did not find any exploit available. Neither in GitHub repositories nor in the Exploit-Database.
Browse More
Continuously monitor your dependencies and get alerted when vulnerabilities like this one affect your stack.
Checkout DevGuard