Dark Reading is part of the Informa Tech Division of Informa PLC

This site is operated by a business or businesses owned by Informa PLC and all copyright resides with them.Informa PLC's registered office is 5 Howick Place, London SW1P 1WG. Registered in England and Wales. Number 8860726.

Comments
RDP Bug Takes New Approach to Host Compromise
Oldest First  |  Newest First  |  Threaded View
tdsan
tdsan,
User Rank: Ninja
7/19/2019 | 5:30:27 PM
Authenticated user, hard to defend against that
The remote code execution bug is in Remote Desktop Services, formerly known as Terminal Services, when an authenticated attacker abuses clipboard redirection.

We have identified ways to address this issue.
# Identify Administrators users
$users = New-Object -TypeName System.Security.Principal.NTAccount ("Administrators")

# Security Principles for users accessing systems
$SIDofSecureUserGroup = $users.Translate([System.Security.Principal.SecurityIdentifier]).Value

# Secure User Groups found in the Administrators Group
$SecureMachineGroupSDDL = "D:(A;;CC;;; $SIDofSecureUserGroup)"

# Remote Desktop DisplayName for individual rules
$rule = (Get-NetFirewallRule -DisplayName "Remote Desktop*").DisplayName
    foreach ($i in $rule) {
        Set-NetFirewallRule -DisplayName $i -Profile "Private"
    }

# Set Remote Desktop, add Builtin\Administrators groups to the filter
$nfSecurityFilter = Get-NetFirewallRule -DisplayName "Remote Desktop*" | Get-NetFirewallSecurityFilter

# Set NetFirewallSecurity Filter Settings for Authorized Users, login required for local users
Set-NetFirewallSecurityFilter -RemoteMachine $SecureMachineGroupSDDL -InputObject $nfSecurityFilter -Authentication Required -Encryption Required

#This cmdlet can be run using only the pipeline.
foreach ($i in $rule) {
    Get-NetFirewallRule -DisplayName $i | Get-NetFirewallSecurityFilter | Set-NetFirewallSecurityFilter -RemoteMachine $SecureMachineGroupSDDL -Authentication Required -Encryption Required
}

#Looks for Remote Desktop rule, then sends the results to a file on your desktop call fwrules.txt (append)

Get-NetFirewallRule -DisplayName "Remote Desktop*" | out-file $env:USERPROFILE\desktop\fwrules.txt -Append
Get-NetFirewallRule -DisplayName "Remote Desktop*" | Get-NetFirewallSecurityFilter | out-file $env:USERPROFILE\desktop\fwfilter.txt -Append

We have implemented this fix on our site, maybe someone from the various teams could utilize this code to ensure RDP is not compomised.

Todd
miha12
miha12,
User Rank: Apprentice
7/20/2019 | 7:36:40 AM
nice post
Amazing work
tdsan
tdsan,
User Rank: Ninja
7/22/2019 | 11:59:46 PM
Re: nice post
Also, one thing about Hyper-V, if we apply the same rules to the Hyper-V environment, we can isolate Hyper-V's use to the localsubnet so no-one outside of the network could access those servers. It could be locked down even further using Encryption and Authentication.

Todd


Edge-DRsplash-10-edge-articles
I Smell a RAT! New Cybersecurity Threats for the Crypto Industry
David Trepp, Partner, IT Assurance with accounting and advisory firm BPM LLP,  7/9/2021
News
Attacks on Kaseya Servers Led to Ransomware in Less Than 2 Hours
Robert Lemos, Contributing Writer,  7/7/2021
Commentary
It's in the Game (but It Shouldn't Be)
Tal Memran, Cybersecurity Expert, CYE,  7/9/2021
Register for Dark Reading Newsletters
White Papers
Video
Cartoon
Current Issue
Incorporating a Prevention Mindset into Threat Detection and Response
Threat detection and response systems, by definition, are reactive because they have to wait for damage to be done before finding the attack. With a prevention-mindset, security teams can proactively anticipate the attacker's next move, rather than reacting to specific threats or trying to detect the latest techniques in real-time. The report covers areas enterprises should focus on: What positive response looks like. Improving security hygiene. Combining preventive actions with red team efforts.
Flash Poll
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
CVE-2022-22497
PUBLISHED: 2022-05-24
IBM Aspera Faspex 4.4.1 and 5.0.0 could allow unauthorized access due to an incorrectly computed security token. IBM X-Force ID: 226951.
CVE-2022-29334
PUBLISHED: 2022-05-24
An issue in H v1.0 allows attackers to bypass authentication via a session replay attack.
CVE-2022-29337
PUBLISHED: 2022-05-24
C-DATA FD702XW-X-R430 v2.1.13_X001 was discovered to contain a command injection vulnerability via the va_cmd parameter in formlanipv6. This vulnerability allows attackers to execute arbitrary commands via a crafted HTTP request.
CVE-2022-29333
PUBLISHED: 2022-05-24
A vulnerability in CyberLink Power Director v14 allows attackers to escalate privileges via a crafted .exe file.
CVE-2021-3597
PUBLISHED: 2022-05-24
A flaw was found in undertow. The HTTP2SourceChannel fails to write the final frame under some circumstances, resulting in a denial of service. The highest threat from this vulnerability is availability. This flaw affects Undertow versions prior to 2.0.35.SP1, prior to 2.2.6.SP1, prior to 2.2.7.SP1,...