Mgetty up to 1.2.0 faxrec.c fax_notify_mail mail_to command injection

Summaryinfo

A vulnerability classified as critical has been found in Mgetty up to 1.2.0. This affects the function fax_notify_mail of the file faxrec.c. Performing a manipulation of the argument mail_to as part of Parameter results in command injection. This vulnerability is identified as CVE-2018-16744. The attack is only possible with local access. There is not any exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical has been found in Mgetty up to 1.2.0. This affects the function fax_notify_mail of the file faxrec.c. The manipulation of the argument mail_to as part of a Parameter leads to a command injection vulnerability. CWE is classifying the issue as CWE-77. The product constructs all or part of a command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended command when it is sent to a downstream component. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

An issue was discovered in mgetty before 1.2.1. In fax_notify_mail() in faxrec.c, the mail_to parameter is not sanitized. It could allow for command injection if untrusted input can reach it, because popen is used.

The bug was discovered 09/11/2018. The weakness was released 09/13/2018 (Website). It is possible to read the advisory at x41-dsec.de. This vulnerability is uniquely identified as CVE-2018-16744 since 09/09/2018. The exploitability is told to be easy. Attacking locally is a requirement. No form of authentication is needed for exploitation. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1202 according to MITRE ATT&CK.

The vulnerability was handled as a non-public zero-day exploit for at least 2 days. During that time the estimated underground price was around $0-$5k. The vulnerability scanner Nessus provides a plugin with the ID 117855 (openSUSE Security Update : mgetty (openSUSE-2018-1080)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family SuSE Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 171593 (SUSE Enterprise Linux Security Update for mgetty (SUSE-SU-2018:2850-1)).

Upgrading to version 1.2.1 eliminates this vulnerability. A possible mitigation has been published 3 weeks after the disclosure of the vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (117855). Entries connected to this vulnerability are available at VDB-124008, VDB-124009, VDB-124010 and VDB-124012. Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Name

• Mgetty

Version

• 1.0
• 1.1
• 1.2.0

CPE 2.3info

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CPE 2.2info

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Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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