High severity · published Jun 21, 2018
CVE-2017-2669
Dovecot before version 2.2.29 is vulnerable to a denial of service
7.5
CVSS
4.5%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)4.5% · higher than 91% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DL
Debian Linux · Debian
8.0 · source: NVD
DO
Dovecot · Dovecot
2.2.26 through 2.2.28 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2017-2669
CVE.org
https://www.cve.org/CVERecord?id=CVE-2017-2669
Mailing List
http://www.openwall.com/lists/oss-security/2017/04/11/1
Third Party Advisory
http://www.securityfocus.com/bid/97536
Issue Tracking
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2017-2669
Vendor Advisory
https://dovecot.org/pipermail/dovecot-news/2017-April/000341.html
Third Party Advisory
https://github.com/dovecot/core/commit/000030feb7a30f193197f1aab8a7b04a26b42735.patch
Third Party Advisory
https://www.debian.org/security/2017/dsa-3828
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