Inter7 Courier-imap up to 2.2.1 Debugging debug.c auth_debug buf format string

CVSS Meta Temp Score
CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.
Current Exploit Price (≈)
Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.
CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.

A vulnerability was found in Inter7 Courier-imap up to 2.2.1. It has been declared as critical. This vulnerability affects the function auth_debug of the file debug.c of the component Debugging Handler. The manipulation of the argument buf with an unknown input leads to a format string vulnerability. The CWE definition for the vulnerability is CWE-134. The product uses a function that accepts a format string as an argument, but the format string originates from an external source. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

Format string vulnerability in the auth_debug function in Courier-IMAP 1.6.0 through 2.2.1 and 3.x through 3.0.3, when login debugging (DEBUG_LOGIN) is enabled, allows remote attackers to execute arbitrary code.

The bug was discovered 08/10/2004. The weakness was presented 08/18/2004 (Website). The advisory is available at This vulnerability was named CVE-2004-0777 since 08/11/2004. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. Technical details and also a public exploit are known.

A public exploit has been developed by ktha in ANSI C and been published immediately after the advisory. It is possible to download the exploit at It is declared as proof-of-concept. The vulnerability was handled as a non-public zero-day exploit for at least 8 days. During that time the estimated underground price was around $0-$5k. The vulnerability scanner Nessus provides a plugin with the ID 14342 (FreeBSD : courier-imap -- format string vulnerability in debug mode (26)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family FreeBSD Local Security Checks.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product. Attack attempts may be identified with Snort ID 2664. Furthermore it is possible to detect and prevent this kind of attack with TippingPoint and the filter 3457.

The vulnerability is also documented in the databases at X-Force (17034), Tenable (14342) and Exploit-DB (432). See VDB-21769 for similar entry.





CPE 2.3info

CPE 2.2info


VulDB CVSS-B Score: 🔍
VulDB CVSS-BT Score: 🔍
VulDB Vector: 🔍
VulDB Reliability: 🔍


VulDB Meta Base Score: 7.3
VulDB Meta Temp Score: 6.9

VulDB Base Score: 7.3
VulDB Temp Score: 6.9
VulDB Vector: 🔍
VulDB Reliability: 🔍



VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍


Class: Format string
CWE: CWE-134 / CWE-119

Local: No
Remote: Yes

Availability: 🔍
Access: Public
Status: Proof-of-Concept
Author: ktha
Programming Language: 🔍
Download: 🔍

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍


Nessus ID: 14342
Nessus Name: FreeBSD : courier-imap -- format string vulnerability in debug mode (26)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍

OpenVAS ID: 52418
OpenVAS Name: FreeBSD Ports: courier-imap
OpenVAS File: 🔍
OpenVAS Family: 🔍

Exploit-DB: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍


Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍
Exploit Delay Time: 🔍
Snort ID: 2664
Snort Message: PROTOCOL-IMAP login format string attempt
Snort Class: 🔍
TippingPoint: 🔍
SourceFire IPS: 🔍


08/10/2004 🔍
08/11/2004 +1 days 🔍
08/18/2004 +7 days 🔍
08/18/2004 +0 days 🔍
08/18/2004 +0 days 🔍
08/18/2004 +0 days 🔍
08/19/2004 +0 days 🔍
08/19/2004 +0 days 🔍
08/23/2004 +3 days 🔍
09/02/2004 +10 days 🔍
09/13/2004 +11 days 🔍
10/20/2004 +37 days 🔍
04/14/2015 +3828 days 🔍
06/22/2024 +3356 days 🔍


Status: Confirmed

CVE: CVE-2004-0777 (🔍)
X-Force: 17034
Vulnerability Center: 5395 - Courier-IMAP 1.6.0 - 3.0.2 r1 Allows Code Execution via auth_debug Function, Medium
SecurityFocus: 10976 - Courier-IMAP Remote Format String Vulnerability
Secunia: 12324 - Courier-IMAP Login Debugging Format String Vulnerability, Less Critical
OSVDB: 9013 - Courier-IMAP debug.c auth_debug() Function Remote Format String

scip Labs:
See also: 🔍


Created: 04/14/2015 01:21 PM
Updated: 06/22/2024 01:10 AM
Changes: 04/14/2015 01:21 PM (75), 08/18/2017 11:22 PM (17), 06/30/2021 10:48 AM (3), 06/22/2024 01:10 AM (15)
Complete: 🔍
Cache ID: 3:6D0:40


No comments yet. Languages: en.

Please log in to comment.

Interested in the pricing of exploits?

See the underground prices here!