Dovecot
Source repositories
CVEs (74)
| CVE | Vendor / Product | Sev | Risk | CVSS | EPSS | KEV | Published | Description |
|---|---|---|---|---|---|---|---|---|
| CVE-2024-23185 | Hig | 0.49 | 7.5 | 0.01 | Sep 10, 2024 | Very large headers can cause resource exhaustion when parsing message. The message-parser normally reads reasonably sized chunks of the message. However, when it feeds them to message-header-parser, it starts building up "full_value" buffer out of the smaller chunks. The… | ||
| CVE-2008-4577 | Hig | 0.49 | 7.5 | 0.02 | Oct 15, 2008 | The ACL plugin in Dovecot before 1.1.4 treats negative access rights as if they are positive access rights, which allows attackers to bypass intended access restrictions. | ||
| CVE-2026-27851 | Hig | 0.48 | 7.4 | 0.00 | May 12, 2026 | When safe filter is used with variable expansion, all following pipelines on the same string are incorrectly interpreted as safe too, enabling unsafe data to be unescaped. This can enable SQL / LDAP injection attacks when used in authentication. Avoid using safe filter until on… | ||
| CVE-2026-33603 | Med | 0.44 | 6.8 | 0.00 | May 12, 2026 | Attacker can use a specially crafted base64 exchange between Dovecot and Client to fake SCRAM TLS channel binding. This requires that the attacker is able to position itself between Dovecot and the client connection. If successful, the attacker can eavesdrop communications… | ||
| CVE-2026-24031 | Hig | 0.43 | 7.7 | 0.00 | Mar 27, 2026 | Dovecot SQL based authentication can be bypassed when auth_username_chars is cleared by admin. This vulnerability allows bypassing authentication for any user and user enumeration. Do not clear auth_username_chars. If this is not possible, install latest fixed version. No… | ||
| CVE-2026-27858 | Hig | 0.42 | 7.5 | 0.00 | Mar 27, 2026 | Attacker can send a specifically crafted message before authentication that causes managesieve to allocate large amount of memory. Attacker can force managesieve-login to be unavailable by repeatedly crashing the process. Protect access to managesieve protocol, or install… | ||
| CVE-2025-59032 | Hig | 0.42 | 7.5 | 0.00 | Mar 27, 2026 | 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… | ||
| CVE-2016-8652 | Med | 0.42 | 5.9 | 0.48 | Feb 17, 2017 | 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. | ||
| CVE-2026-27856 | Hig | 0.41 | 7.4 | 0.00 | Mar 27, 2026 | Doveadm credentials are verified using direct comparison which is susceptible to timing oracle attack. An attacker can use this to determine the configured credentials. Figuring out the credential will lead into full access to the affected component. Limit access to the doveadm… | ||
| CVE-2017-14461 | Med | 0.40 | 5.9 | 0.18 | Mar 2, 2018 | A specially crafted email delivered over SMTP and passed on to Dovecot by MTA can trigger an out of bounds read resulting in potential sensitive information disclosure and denial of service. In order to trigger this vulnerability, an attacker needs to send a specially crafted… | ||
| CVE-2017-15130 | Med | 0.39 | 5.9 | 0.03 | Mar 2, 2018 | A denial of service flaw was found in dovecot before 2.2.34. An attacker able to generate random SNI server names could exploit TLS SNI configuration lookups, leading to excessive memory usage and the process to restart. | ||
| CVE-2015-3420 | Med | 0.39 | 5.9 | 0.03 | Sep 19, 2017 | The ssl-proxy-openssl.c function in Dovecot before 2.2.17, when SSLv3 is disabled, allow remote attackers to cause a denial of service (login process crash) via vectors related to handshake failures. | ||
| CVE-2026-27855 | Med | 0.37 | 6.8 | 0.00 | Mar 27, 2026 | Dovecot OTP authentication is vulnerable to replay attack under specific conditions. If auth cache is enabled, and username is altered in passdb, then OTP credentials can be cached so that same OTP reply is valid. An attacker able to observe an OTP exchange is able to log in as… | ||
| CVE-2009-3897 | Med | 0.36 | 5.5 | 0.00 | Nov 24, 2009 | Dovecot 1.2.x before 1.2.8 sets 0777 permissions during creation of certain directories at installation time, which allows local users to access arbitrary user accounts by replacing the auth socket, related to the parent directories of the base_dir directory, and possibly the… | ||
| CVE-2026-40016 | Med | 0.34 | 5.3 | 0.00 | May 12, 2026 | Attacker can upload a malicious Sieve script over ManageSieve service (or locally) to bypass configured CPU time limits for Sieve up to 130 times of the configured limit. Attacker can use this to degrade server performance and bypass configured CPU time limits for Sieve scripts.… | ||
| CVE-2024-25584 | Med | 0.34 | 5.3 | 0.00 | Sep 6, 2024 | Dovecot accepts dot LF DOT LF symbol as end of DATA command. RFC requires that it should always be CR LF DOT CR LF. This causes Dovecot to convert single mail with LF DOT LF in middle, into two emails when relaying to SMTP. Dovecot will split mail with LF DOT LF into two mails.… | ||
| CVE-2024-23184 | Med | 0.33 | 5.0 | 0.01 | Sep 10, 2024 | Having a large number of address headers (From, To, Cc, Bcc, etc.) becomes excessively CPU intensive. With 100k header lines CPU usage is already 12 seconds, and in a production environment we observed 500k header lines taking 18 minutes to parse. Since this can be triggered by… | ||
| CVE-2026-27859 | Med | 0.27 | 5.3 | 0.00 | Mar 27, 2026 | A mail message containing excessive amount of RFC 2231 MIME parameters causes LMTP to use too much CPU. A suitably formatted mail message causes mail delivery process to consume large amounts of CPU time. Use MTA capabilities to limit RFC 2231 MIME parameters in mail messages,… | ||
| CVE-2026-0394 | Med | 0.27 | 5.3 | 0.00 | Mar 27, 2026 | When dovecot has been configured to use per-domain passwd files, and they are placed one path component above /etc, or slash has been added to allowed characters, path traversal can happen if the domain component is directory partial. This allows inadvertently reading… | ||
| CVE-2025-59028 | Med | 0.27 | 5.3 | 0.00 | Mar 27, 2026 | 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… |
- risk 0.49cvss 7.5epss 0.01
Very large headers can cause resource exhaustion when parsing message. The message-parser normally reads reasonably sized chunks of the message. However, when it feeds them to message-header-parser, it starts building up "full_value" buffer out of the smaller chunks. The…
- risk 0.49cvss 7.5epss 0.02
The ACL plugin in Dovecot before 1.1.4 treats negative access rights as if they are positive access rights, which allows attackers to bypass intended access restrictions.
- risk 0.48cvss 7.4epss 0.00
When safe filter is used with variable expansion, all following pipelines on the same string are incorrectly interpreted as safe too, enabling unsafe data to be unescaped. This can enable SQL / LDAP injection attacks when used in authentication. Avoid using safe filter until on…
- risk 0.44cvss 6.8epss 0.00
Attacker can use a specially crafted base64 exchange between Dovecot and Client to fake SCRAM TLS channel binding. This requires that the attacker is able to position itself between Dovecot and the client connection. If successful, the attacker can eavesdrop communications…
- risk 0.43cvss 7.7epss 0.00
Dovecot SQL based authentication can be bypassed when auth_username_chars is cleared by admin. This vulnerability allows bypassing authentication for any user and user enumeration. Do not clear auth_username_chars. If this is not possible, install latest fixed version. No…
- risk 0.42cvss 7.5epss 0.00
Attacker can send a specifically crafted message before authentication that causes managesieve to allocate large amount of memory. Attacker can force managesieve-login to be unavailable by repeatedly crashing the process. Protect access to managesieve protocol, or install…
- risk 0.42cvss 7.5epss 0.00
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…
- risk 0.42cvss 5.9epss 0.48
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.
- risk 0.41cvss 7.4epss 0.00
Doveadm credentials are verified using direct comparison which is susceptible to timing oracle attack. An attacker can use this to determine the configured credentials. Figuring out the credential will lead into full access to the affected component. Limit access to the doveadm…
- risk 0.40cvss 5.9epss 0.18
A specially crafted email delivered over SMTP and passed on to Dovecot by MTA can trigger an out of bounds read resulting in potential sensitive information disclosure and denial of service. In order to trigger this vulnerability, an attacker needs to send a specially crafted…
- risk 0.39cvss 5.9epss 0.03
A denial of service flaw was found in dovecot before 2.2.34. An attacker able to generate random SNI server names could exploit TLS SNI configuration lookups, leading to excessive memory usage and the process to restart.
- risk 0.39cvss 5.9epss 0.03
The ssl-proxy-openssl.c function in Dovecot before 2.2.17, when SSLv3 is disabled, allow remote attackers to cause a denial of service (login process crash) via vectors related to handshake failures.
- risk 0.37cvss 6.8epss 0.00
Dovecot OTP authentication is vulnerable to replay attack under specific conditions. If auth cache is enabled, and username is altered in passdb, then OTP credentials can be cached so that same OTP reply is valid. An attacker able to observe an OTP exchange is able to log in as…
- risk 0.36cvss 5.5epss 0.00
Dovecot 1.2.x before 1.2.8 sets 0777 permissions during creation of certain directories at installation time, which allows local users to access arbitrary user accounts by replacing the auth socket, related to the parent directories of the base_dir directory, and possibly the…
- risk 0.34cvss 5.3epss 0.00
Attacker can upload a malicious Sieve script over ManageSieve service (or locally) to bypass configured CPU time limits for Sieve up to 130 times of the configured limit. Attacker can use this to degrade server performance and bypass configured CPU time limits for Sieve scripts.…
- risk 0.34cvss 5.3epss 0.00
Dovecot accepts dot LF DOT LF symbol as end of DATA command. RFC requires that it should always be CR LF DOT CR LF. This causes Dovecot to convert single mail with LF DOT LF in middle, into two emails when relaying to SMTP. Dovecot will split mail with LF DOT LF into two mails.…
- risk 0.33cvss 5.0epss 0.01
Having a large number of address headers (From, To, Cc, Bcc, etc.) becomes excessively CPU intensive. With 100k header lines CPU usage is already 12 seconds, and in a production environment we observed 500k header lines taking 18 minutes to parse. Since this can be triggered by…
- risk 0.27cvss 5.3epss 0.00
A mail message containing excessive amount of RFC 2231 MIME parameters causes LMTP to use too much CPU. A suitably formatted mail message causes mail delivery process to consume large amounts of CPU time. Use MTA capabilities to limit RFC 2231 MIME parameters in mail messages,…
- risk 0.27cvss 5.3epss 0.00
When dovecot has been configured to use per-domain passwd files, and they are placed one path component above /etc, or slash has been added to allowed characters, path traversal can happen if the domain component is directory partial. This allows inadvertently reading…
- risk 0.27cvss 5.3epss 0.00
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…
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