Cyrus IMAPd NNTP AUTHINFO USER Command Parsing Authentication Bypass

medium Nessus Plugin ID 57336
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The remote NNTP server is affected by an authentication bypass vulnerability.


The remote NNTP server contains a logic error that causes clients that send only a username, neglecting to send a password, to be treated as authenticated. This may permit an unauthenticated, remote attacker to view and post to restricted newsgroups, impersonating other users in the process.


Upgrade Cyrus IMAPd to version 2.4.12 or later.

See Also

Plugin Details

Severity: Medium

ID: 57336

File Name: cyrus_imap_nntp_auth_bypass.nasl

Version: 1.8

Type: remote

Family: General

Published: 12/19/2011

Updated: 2/24/2021

Dependencies: nntp_anonymous.nasl

Risk Information

CVSS Score Source: manual

CVSS Score Rationale: Based on analysis of vulnerability


Risk Factor: Medium

Score: 5.9


Risk Factor: Medium

Base Score: 6.4

Temporal Score: 4.7

Vector: AV:N/AC:L/Au:N/C:P/I:P/A:N

Temporal Vector: E:U/RL:OF/RC:C

Vulnerability Information

CPE: cpe:/a:cmu:cyrus_imap_server

Exploit Ease: No known exploits are available

Patch Publication Date: 10/4/2011

Vulnerability Publication Date: 10/4/2011

Reference Information

CVE: CVE-2011-3372

BID: 49949