nginx up to 1.7.3 SMTP Proxy ngx_mail_smtp_starttls STARTTLS command injection

CVSS Meta Temp Score
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CTI Interest Score
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4.6$0-$5k0.00

A vulnerability, which was classified as critical, was found in nginx (Web Server). Affected is the function ngx_mail_smtp_starttls of the component SMTP Proxy. The manipulation of the argument STARTTLS with an unknown input 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.

The weakness was released 08/05/2014 by Chris Boulton as nginx security advisory (CVE-2014-3556) as confirmed advisory (Mailing List). The advisory is shared for download at mailman.nginx.org. The public release was coordinated with the vendor. This vulnerability is traded as CVE-2014-3556 since 05/14/2014. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. There are known technical details, but no exploit is available. The MITRE ATT&CK project declares the attack technique as T1202.

The vulnerability scanner Nessus provides a plugin with the ID 77109 (FreeBSD : nginx -- inject commands into SSL session vulnerability (ad747a01-1fee-11e4-8ff1-f0def16c5c1b)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family FreeBSD Local Security Checks. The commercial vulnerability scanner Qualys is able to test this issue with plugin 13267 (Nginx STARTTLS Command Injection Vulnerability).

Upgrading to version 1.6.1 or 1.7.4 eliminates this vulnerability. Applying a patch is able to eliminate this problem. The bugfix is ready for download at nginx.org. The best possible mitigation is suggested to be upgrading to the latest version. A possible mitigation has been published immediately after the disclosure of the vulnerability. The vulnerability will be addressed with the following lines of code:

s->buffer->pos = s->buffer->start;
s->buffer->last = s->buffer->start;
Furthermore it is possible to detect and prevent this kind of attack with TippingPoint and the filter 11309.

The vulnerability is also documented in the databases at X-Force (95167) and Tenable (77109).

Productinfo

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Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB CVSS-B Score: 🔍
VulDB CVSS-BT Score: 🔍
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CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 4.6

VulDB Base Score: 5.3
VulDB Temp Score: 4.6
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
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NVD Base Score: 🔍

Exploitinginfo

Class: Command injection
CWE: CWE-77 / CWE-74 / CWE-707
ATT&CK: T1202

Local: No
Remote: Yes

Availability: 🔍
Status: Unproven

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 77109
Nessus Name: FreeBSD : nginx -- inject commands into SSL session vulnerability (ad747a01-1fee-11e4-8ff1-f0def16c5c1b)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Port: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍

Upgrade: nginx 1.6.1/1.7.4
Patch: nginx.org
TippingPoint: 🔍

Timelineinfo

05/14/2014 🔍
08/05/2014 +83 days 🔍
08/05/2014 +0 days 🔍
08/07/2014 +2 days 🔍
08/07/2014 +0 days 🔍
08/07/2014 +0 days 🔍
08/08/2014 +1 days 🔍
08/10/2014 +2 days 🔍
08/14/2014 +4 days 🔍
12/29/2014 +137 days 🔍
02/10/2022 +2600 days 🔍

Sourcesinfo

Advisory: nginx security advisory (CVE-2014-3556)
Researcher: Chris Boulton
Status: Confirmed
Confirmation: 🔍
Coordinated: 🔍

CVE: CVE-2014-3556 (🔍)
X-Force: 95167 - nginx ngx_mail_smtp_starttls() command execution, High Risk
SecurityTracker: 1030692 - nginx SMTP Proxy STARTTLS Flaw Lets Remote Users Inject Commands into SSL Sessions to Obtain Potentially Sensitive Information
Vulnerability Center: 45839 - nginx Remote Information Disclosure via Injecting Commands into SSL Sessions, Medium
SecurityFocus: 69111 - nginx SMTP Proxy Remote Command Injection Vulnerability

Entryinfo

Created: 08/08/2014 10:16
Updated: 02/10/2022 09:02
Changes: 08/08/2014 10:16 (84), 06/04/2017 10:49 (2), 02/10/2022 08:58 (3), 02/10/2022 09:02 (1)
Complete: 🔍

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