Rule Category

SERVER-MAIL -- Snort has detected traffic exploiting vulnerabilities in mail servers (such as Exchange, Courrier). These are different from protocol traffic, as this deals with the traffic going to the mail server itself.

Alert Message

SERVER-MAIL AUTH user overflow attempt

Rule Explanation

Buffer overflow in the spa_base64_to_bits function in Exim before 4.43, as originally obtained from Samba code, and as called by the auth_spa_client function, may allow attackers to execute arbitrary code during SPA authentication. Impact: CVSS base score 4.6 CVSS impact score 6.4 CVSS exploitability score 3.9 confidentialityImpact PARTIAL integrityImpact PARTIAL availabilityImpact PARTIAL Details: Ease of Attack:

What To Look For

Known Usage

No public information

False Positives

No known false positives

Contributors

Talos research team. This document was generated from data supplied by the national vulnerability database, a product of the national institute of standards and technology. For more information see [nvd].

MITRE ATT&CK Framework

Tactic:

Technique:

For reference, see the MITRE ATT&CK vulnerability types here: https://attack.mitre.org

CVE

Rule Vulnerability

CVE Additional Information

CVE-2005-0022
Buffer overflow in the spa_base64_to_bits function in Exim before 4.43, as originally obtained from Samba code, and as called by the auth_spa_client function, may allow attackers to execute arbitrary code during SPA authentication.
Details
SeverityMEDIUM Base Score4.6
Impact Score6.4 Exploit Score3.9
Confidentiality ImpactPARTIAL Integrity ImpactPARTIAL
Availability ImpactPARTIAL Access Vector
AuthenticationNONE Ease of Access
CVE-2005-1781
Unknown vulnerability in SMTP authentication for MailEnable allows remote attackers to cause a denial of service (crash).
Details
SeverityMEDIUM Base Score5.0
Impact Score2.9 Exploit Score10.0
Confidentiality ImpactNONE Integrity ImpactNONE
Availability ImpactPARTIAL Access Vector
AuthenticationNONE Ease of Access
CVE-2005-2223
Unknown vulnerability in the SMTP service in MailEnable Standard before 1.9 and Professional before 1.6 allows remote attackers to cause a denial of service (crash) during authentication.
Details
SeverityMEDIUM Base Score5.0
Impact Score2.9 Exploit Score10.0
Confidentiality ImpactNONE Integrity ImpactNONE
Availability ImpactPARTIAL Access Vector
AuthenticationNONE Ease of Access
CVE-2006-5478
Multiple stack-based buffer overflows in Novell eDirectory 8.8.x before 8.8.1 FTF1, and 8.x up to 8.7.3.8, and Novell NetMail before 3.52e FTF2, allow remote attackers to execute arbitrary code via (1) a long HTTP Host header, which triggers an overflow in the BuildRedirectURL function; or vectors related to a username containing a . (dot) character in the (2) SMTP, (3) POP, (4) IMAP, (5) HTTP, or (6) Networked Messaging Application Protocol (NMAP) Netmail services.
Details
SeverityHIGH Base Score7.5
Impact Score6.4 Exploit Score10.0
Confidentiality ImpactPARTIAL Integrity ImpactPARTIAL
Availability ImpactPARTIAL Access Vector
AuthenticationNONE Ease of Access
CVE-2007-4440
Stack-based buffer overflow in the MercuryS SMTP server in Mercury Mail Transport System, possibly 4.51 and earlier, allows remote attackers to execute arbitrary code via a long AUTH CRAM-MD5 string. NOTE: this might overlap CVE-2006-5961.
Details
SeverityHIGH Base Score7.5
Impact Score6.4 Exploit Score10.0
Confidentiality ImpactPARTIAL Integrity ImpactPARTIAL
Availability ImpactPARTIAL Access Vector
AuthenticationNONE Ease of Access
CVE-2018-6789
An issue was discovered in the base64d function in the SMTP listener in Exim before 4.90.1. By sending a handcrafted message, a buffer overflow may happen. This can be used to execute code remotely.
Details
Severity Base Score9.8
Impact Score5.9 Exploit Score3.9
Confidentiality ImpactHIGH Integrity ImpactHIGH
Availability ImpactHIGH Access Vector
Authentication Ease of Access