description: 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.
problem types: CWE-20
affected:
{
product: dovecot
vendor: [UNKNOWN]
versions:
status: affected, version: dovecot 2.2.29
}
metrics:
cvssV3_0: [
attackComplexity: HIGH
attackVector: NETWORK
availabilityImpact: LOW
baseScore: 3.7
baseSeverity: LOW
confidentialityImpact: NONE
integrityImpact: NONE
privilegesRequired: NONE
scope: UNCHANGED
userInteraction: NONE
vectorString: CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L
version: 3.0
]