In Dovecot before 2.3.10.1, remote unauthenticated attackers can crash the lmtp or submission process by sending mail with an empty localpart.

lib-mail/message-header-parser.c in Dovecot 1.2.x before 1.2.17 and 2.0.x before 2.0.13 does not properly handle '\0' characters in header names, which allows remote attackers to cause a denial of service (daemon crash or mailbox corruption) via a crafted e-mail message.

Dovecot before version 2.2.29 is vulnerable to a denial of service. When 'dict' passdb and userdb were used for user authentication, the username sent by the IMAP/POP3 client was sent through var_expand() to perform %variable expansion. Sending specially crafted %variable fields could result in excessive memory usage causing the process to crash (and restart), or excessive CPU usage causing all authentications to hang.

The IMAP and LMTP components in Dovecot 2.3.9 before 2.3.9.3 mishandle snippet generation when many characters must be read to compute the snippet and a trailing > character exists. This causes a denial of service in which the recipient cannot read all of their messages.

Dovecot before 2.3.13 has Improper Input Validation in lda, lmtp, and imap, leading to an application crash via a crafted email message with certain choices for ten thousand MIME parts.

Unspecified vulnerability in Dovecot 1.2.x before 1.2.11 allows remote attackers to cause a denial of service (CPU consumption) via long headers in an e-mail message.

In the IMAP Server in Dovecot 2.3.3 through 2.3.5.2, the submission-login component crashes if AUTH PLAIN is attempted over a TLS secured channel with an unacceptable authentication message.

In the IMAP Server in Dovecot 2.3.3 through 2.3.5.2, the submission-login service crashes when the client disconnects prematurely during the AUTH command.

The JSON encoder in Dovecot before 2.3.5.2 allows attackers to repeatedly crash the authentication service by attempting to authenticate with an invalid UTF-8 sequence as the username.

A flaw was found in dovecot 2.0 up to 2.2.33 and 2.3.0. An abort of SASL authentication results in a memory leak in dovecot's auth client used by login processes. The leak has impact in high performance configuration where same login processes are reused and can cause the process to crash due to memory exhaustion.

Dovecot 1.1 before 2.2.13 and dovecot-ee before 2.1.7.7 and 2.2.x before 2.2.12.12 does not properly close old connections, which allows remote attackers to cause a denial of service (resource consumption) via an incomplete SSL/TLS handshake for an IMAP/POP3 connection.

In Dovecot before 2.3.11.3, sending a specially formatted NTLM request will crash the auth service because of an out-of-bounds read.

In Dovecot before 2.3.11.3, sending a specially formatted RPA request will crash the auth service because a length of zero is mishandled.

In Dovecot before 2.3.11.3, uncontrolled recursion in submission, lmtp, and lda allows remote attackers to cause a denial of service (resource consumption) via a crafted e-mail message with deeply nested MIME parts.

In Dovecot before 2.3.10.1, unauthenticated sending of malformed parameters to a NOOP command causes a NULL Pointer Dereference and crash in submission-login, submission, or lmtp.

In Dovecot before 2.3.10.1, a crafted SMTP/LMTP message triggers an unauthenticated use-after-free bug in submission-login, submission, or lmtp, and can lead to a crash under circumstances involving many newlines after a command.

In Dovecot before 2.3.9.2, an attacker can crash a push-notification driver with a crafted email when push notifications are used, because of a NULL Pointer Dereference. The email must use a group address as either the sender or the recipient.

Dovecot 2.0.x before 2.0.16, when ssl or starttls is enabled and hostname is used to define the proxy destination, does not verify that the server hostname matches a domain name in the subject's Common Name (CN) of the X.509 certificate, which allows man-in-the-middle attackers to spoof SSL servers via a valid certificate for a different hostname.

The auth component in Dovecot before 2.2.27, when auth-policy is configured, allows a remote attackers to cause a denial of service (crash) by aborting authentication without setting a username.

When sending invalid base64 SASL data, login process is disconnected from the auth server, causing all active authentication sessions to fail. Invalid BASE64 data can be used to DoS a vulnerable server to break concurrent logins. Install fixed version or disable concurrency in login processes (heavy perfomance penalty on large deployments). No publicly available exploits are known.

ManageSieve AUTHENTICATE command crashes when using literal as SASL initial response. This can be used to crash ManageSieve service repeatedly, making it unavailable for other users. Control access to ManageSieve port, or disable the service if it's not needed. Alternatively upgrade to a fixed version. No publicly available exploits are known.

The message parsing feature in Dovecot 1.1.4 and 1.1.5, when using the FETCH ENVELOPE command in the IMAP client, allows remote attackers to cause a denial of service (persistent crash) via an email with a malformed From address, which triggers an assertion error, aka "invalid message address parsing bug."

The Linux implementation of the ICMP-MIB in Net-SNMP 5.5 before 5.5.2.1, 5.6.x before 5.6.2.1, and 5.7.x before 5.7.2.1 does not properly validate input, which allows remote attackers to cause a denial of service via unspecified vectors.

Openswan 2.6.40 allows remote attackers to cause a denial of service (NULL pointer dereference and IKE daemon restart) via IKEv2 packets that lack expected payloads. NOTE: this vulnerability exists because of an incomplete fix for CVE 2013-6466.

Heimdal, as used in Apple OS X through 10.9.2, allows remote attackers to cause a denial of service (abort and daemon exit) via ASN.1 data encountered in the Kerberos 5 protocol.

The base64DecodeInternal function in wtf/text/Base64.cpp in Blink, as used in Google Chrome before 34.0.1847.116, does not properly handle string data composed exclusively of whitespace characters, which allows remote attackers to cause a denial of service (out-of-bounds read) via a window.atob method call.

Triangle MicroWorks SCADA Data Gateway before 3.00.0635 allows remote attackers to cause a denial of service (excessive data processing) via a crafted DNP3 packet.

The AgentX subagent in Net-SNMP before 5.4.4 allows remote attackers to cause a denial of service (hang) by sending a multi-object request with an Object ID (OID) containing more subids than previous requests, a different vulnerability than CVE-2012-6151.

A vulnerability in the web-based management interface of Cisco AsyncOS for Cisco Email Security Appliance (ESA), Cisco Web Security Appliance (WSA), and Cisco Content Security Management Appliance (SMA) could allow an unauthenticated remote attacker to cause high CPU usage on an affected device, resulting in a denial of service (DoS) condition. The vulnerability is due to improper validation of specific HTTP request headers. An attacker could exploit this vulnerability by sending a malformed HTTP request to an affected device. A successful exploit could allow the attacker to trigger a prolonged status of high CPU utilization relative to the GUI process(es). Upon successful exploitation of this vulnerability, an affected device will still be operative, but its response time and overall performance may be degraded.

The Java-based software in Cisco Hosted Collaboration Solution (HCS) allows remote attackers to cause a denial of service (closing of TCP ports) via unspecified vectors, aka Bug IDs CSCug77633, CSCug77667, CSCug78266, CSCug82795, and CSCuh58643.

The DHCPv6 server module in Cisco CNS Network Registrar 7.1 allows remote attackers to cause a denial of service (daemon reload) via a malformed DHCPv6 packet, aka Bug ID CSCuo07437.

Hash#slice in lib/i18n/core_ext/hash.rb in the i18n gem before 0.8.0 for Ruby allows remote attackers to cause a denial of service (application crash) via a call in a situation where :some_key is present in keep_keys but not present in the hash.

A vulnerability in the Event Management Service daemon (emsd) of Cisco IOS XR Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to improper handling of gRPC requests. An attacker could exploit this vulnerability by repeatedly sending unauthenticated gRPC requests to the affected device. A successful exploit could cause the emsd process to crash, resulting in a DoS condition. Resolved in Cisco IOS XR 6.5.1 and later.

Microsoft Windows Server 2008 SP2 and R2 SP1 and Server 2012 Gold and R2 allow remote attackers to cause a denial of service (iSCSI service outage) by sending many crafted packets, aka "iSCSI Target Remote Denial of Service Vulnerability."

The Standalone Enqueue Server in SAP Netweaver 7.20, 7.01, and earlier allows remote attackers to cause a denial of service (uncontrolled recursion and crash) via a trace level with a wildcard in the Trace Pattern.

PerlRun.pm in Apache mod_perl before 1.30, and RegistryCooker.pm in mod_perl 2.x, does not properly escape PATH_INFO before use in a regular expression, which allows remote attackers to cause a denial of service (resource consumption) via a crafted URI.

The server in EMC RSA BSAFE Micro Edition Suite (MES) 4.0.x before 4.0.5 does not properly process certificate chains, which allows remote attackers to cause a denial of service (daemon crash) via unspecified vectors.

An issue was discovered in the once_cell crate before 1.0.1 for Rust. There is a panic during initialization of Lazy.

The internal DNS server in Samba 4.x before 4.0.18 does not check the QR field in the header section of an incoming DNS message before sending a response, which allows remote attackers to cause a denial of service (CPU and bandwidth consumption) via a forged response packet that triggers a communication loop, a related issue to CVE-1999-0103.

The Label Distribution Protocol (LDP) functionality in Cisco NX-OS allows remote attackers to cause a denial of service (temporary LDP session outage) via LDP discovery traffic containing malformed Hello messages, aka Bug ID CSCul88851.

Knot DNS before 1.5.2 allows remote attackers to cause a denial of service (application crash) via a crafted DNS message.

Microsoft .NET Framework 1.1 SP1, 2.0 SP2, 3.5, 3.5.1, 4, 4.5, and 4.5.1 does not properly determine TCP connection states, which allows remote attackers to cause a denial of service (ASP.NET daemon hang) via crafted HTTP requests that trigger persistent resource consumption for a (1) stale or (2) closed connection, as exploited in the wild in February 2014, aka "POST Request DoS Vulnerability."

Microsoft Windows Server 2008 SP2 and R2 SP1 and Server 2012 Gold allow remote attackers to cause a denial of service (iSCSI service outage) by sending many crafted packets, aka "iSCSI Target Remote Denial of Service Vulnerability."

The SNMP module in Cisco IOS XR allows remote attackers to cause a denial of service (process reload) via a request for an unspecified MIB, aka Bug ID CSCuh43144.

The dissect_sip_common function in epan/dissectors/packet-sip.c in the SIP dissector in Wireshark 1.8.x before 1.8.12 and 1.10.x before 1.10.4 does not check for empty lines, which allows remote attackers to cause a denial of service (infinite loop) via a crafted packet.

The ValidateUserLogon function in provider/libserver/ECSession.cpp in Zarafa 5.00 before 7.1.8 beta2 allows remote attackers to cause a denial of service (crash) via vectors related to "a NULL pointer of the username."

Squid 3.1 before 3.3.12 and 3.4 before 3.4.4, when SSL-Bump is enabled, allows remote attackers to cause a denial of service (assertion failure) via a crafted range request, related to state management.

config/filter.d/cyrus-imap.conf in the cyrus-imap filter in Fail2ban before 0.8.11 allows remote attackers to trigger the blocking of an arbitrary IP address via a crafted e-mail address that matches an improperly designed regular expression.

The ValidateUserLogon function in provider/libserver/ECSession.cpp in Zarafa 7.1.8, 6.20.0, and earlier, when using certain build conditions, allows remote attackers to cause a denial of service (crash) via vectors related to "a NULL pointer of the password."

actionpack/lib/action_view/template/text.rb in Action View in Ruby on Rails 3.x before 3.2.17 converts MIME type strings to symbols during use of the :text option to the render method, which allows remote attackers to cause a denial of service (memory consumption) by including these strings in headers.