3.7Low

CVE-2017-2669

[UNKNOWN] dovecot Published: 2018-06-21 16:00 (8 years ago)

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.

Weakness (CWE): CWE-20

Data: CVE.org, NVD, CISA KEV, FIRST EPSS, Ubuntu. Published as the sources state it, in English.

Affected products and versions

Vendor	Product	Versions
—	dovecot	dovecot 2.2.29

References and patches

[dovecot-news] 20170410 v2.2.29 released mailing-list
[oss-security] 20170411 CVE-2017-2669: Dovecot DoS when passdb dict was used for authentication mailing-list
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2017-2669
https://github.com/dovecot/core/commit/000030feb7a30f193197f1aab8a7b04a26b42735.patch
DSA-3828 vendor-advisory
97536 vdb-entry

CVSS score

3.7Low

Source: redhat · CVSS 3.0

Attack vector: Network
Attack complexity: High
Privileges required: None
User interaction: None
Scope: Unchanged
Confidentiality: None
Integrity: None
Availability: Low

CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L

EPSS (chance of exploitation in 30 days)

4.31%

higher than 91% of all CVEs

Timeline

ID reserved2016-12-01
Published2018-06-21 16:00
Reached IP-DB2026-10-24 23:50
Last updated2024-08-05 17:02

Assigned by (CNA): redhat

View at source: CVE.org · NVD

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