Vulnerabilities > CVE-2017-3733 - Improper Input Validation vulnerability in multiple products
Attack vector
NETWORK Attack complexity
LOW Privileges required
NONE Confidentiality impact
NONE Integrity impact
NONE Availability impact
HIGH Summary
During a renegotiation handshake if the Encrypt-Then-Mac extension is negotiated where it was not in the original handshake (or vice-versa) then this can cause OpenSSL 1.1.0 before 1.1.0e to crash (dependent on ciphersuite). Both clients and servers are affected.
Vulnerable Configurations
| Part | Description | Count |
|---|---|---|
| Application | 5 | |
| Application | 2 |
Common Weakness Enumeration (CWE)
Common Attack Pattern Enumeration and Classification (CAPEC)
- Buffer Overflow via Environment Variables This attack pattern involves causing a buffer overflow through manipulation of environment variables. Once the attacker finds that they can modify an environment variable, they may try to overflow associated buffers. This attack leverages implicit trust often placed in environment variables.
- Server Side Include (SSI) Injection An attacker can use Server Side Include (SSI) Injection to send code to a web application that then gets executed by the web server. Doing so enables the attacker to achieve similar results to Cross Site Scripting, viz., arbitrary code execution and information disclosure, albeit on a more limited scale, since the SSI directives are nowhere near as powerful as a full-fledged scripting language. Nonetheless, the attacker can conveniently gain access to sensitive files, such as password files, and execute shell commands.
- Cross Zone Scripting An attacker is able to cause a victim to load content into their web-browser that bypasses security zone controls and gain access to increased privileges to execute scripting code or other web objects such as unsigned ActiveX controls or applets. This is a privilege elevation attack targeted at zone-based web-browser security. In a zone-based model, pages belong to one of a set of zones corresponding to the level of privilege assigned to that page. Pages in an untrusted zone would have a lesser level of access to the system and/or be restricted in the types of executable content it was allowed to invoke. In a cross-zone scripting attack, a page that should be assigned to a less privileged zone is granted the privileges of a more trusted zone. This can be accomplished by exploiting bugs in the browser, exploiting incorrect configuration in the zone controls, through a cross-site scripting attack that causes the attackers' content to be treated as coming from a more trusted page, or by leveraging some piece of system functionality that is accessible from both the trusted and less trusted zone. This attack differs from "Restful Privilege Escalation" in that the latter correlates to the inadequate securing of RESTful access methods (such as HTTP DELETE) on the server, while cross-zone scripting attacks the concept of security zones as implemented by a browser.
- Cross Site Scripting through Log Files An attacker may leverage a system weakness where logs are susceptible to log injection to insert scripts into the system's logs. If these logs are later viewed by an administrator through a thin administrative interface and the log data is not properly HTML encoded before being written to the page, the attackers' scripts stored in the log will be executed in the administrative interface with potentially serious consequences. This attack pattern is really a combination of two other attack patterns: log injection and stored cross site scripting.
- Command Line Execution through SQL Injection An attacker uses standard SQL injection methods to inject data into the command line for execution. This could be done directly through misuse of directives such as MSSQL_xp_cmdshell or indirectly through injection of data into the database that would be interpreted as shell commands. Sometime later, an unscrupulous backend application (or could be part of the functionality of the same application) fetches the injected data stored in the database and uses this data as command line arguments without performing proper validation. The malicious data escapes that data plane by spawning new commands to be executed on the host.
Nessus
NASL family Web Servers NASL id OPENSSL_1_1_0E.NASL description According to its banner, the version of OpenSSL running on the remote host is 1.1.0 prior to 1.1.0e. It is, therefore, affected by a denial of service vulnerability that is triggered during a renegotiation handshake in which the Encrypt-Then-Mac extension is negotiated when it was not in the original handshake or vice-versa. An unauthenticated, remote attacker can exploit this issue to cause OpenSSL to crash, depending on which cipher suite is being used. Note that both clients and servers are affected. last seen 2020-06-01 modified 2020-06-02 plugin id 97328 published 2017-02-23 reporter This script is Copyright (C) 2017-2019 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/97328 title OpenSSL 1.1.0 < 1.1.0e Encrypt-Then-Mac Extension DoS code # # (C) Tenable Network Security, Inc. # include("compat.inc"); if (description) { script_id(97328); script_version("1.6"); script_cvs_date("Date: 2019/11/13"); script_cve_id("CVE-2017-3733"); script_name(english:"OpenSSL 1.1.0 < 1.1.0e Encrypt-Then-Mac Extension DoS"); script_summary(english:"Performs a banner check."); script_set_attribute(attribute:"synopsis", value: "A service running on the remote host is affected by a denial of service vulnerability."); script_set_attribute(attribute:"description", value: "According to its banner, the version of OpenSSL running on the remote host is 1.1.0 prior to 1.1.0e. It is, therefore, affected by a denial of service vulnerability that is triggered during a renegotiation handshake in which the Encrypt-Then-Mac extension is negotiated when it was not in the original handshake or vice-versa. An unauthenticated, remote attacker can exploit this issue to cause OpenSSL to crash, depending on which cipher suite is being used. Note that both clients and servers are affected."); script_set_attribute(attribute:"see_also", value:"https://www.openssl.org/news/secadv/20170216.txt"); script_set_attribute(attribute:"solution", value: "Upgrade to OpenSSL version 1.1.0e or later."); script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P"); script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C"); script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"); script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C"); script_set_attribute(attribute:"cvss_score_source", value:"CVE-2017-3733"); script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available"); script_set_attribute(attribute:"exploit_available", value:"false"); script_set_attribute(attribute:"vuln_publication_date", value:"2017/02/16"); script_set_attribute(attribute:"patch_publication_date", value:"2017/02/16"); script_set_attribute(attribute:"plugin_publication_date", value:"2017/02/23"); script_set_attribute(attribute:"plugin_type", value:"remote"); script_set_attribute(attribute:"cpe", value:"cpe:/a:openssl:openssl"); script_end_attributes(); script_category(ACT_GATHER_INFO); script_family(english:"Web Servers"); script_copyright(english:"This script is Copyright (C) 2017-2019 and is owned by Tenable, Inc. or an Affiliate thereof."); script_dependencies("openssl_version.nasl"); script_require_keys("openssl/port"); exit(0); } include("openssl_version.inc"); openssl_check_version(fixed:'1.1.0e', min:"1.1.0", severity:SECURITY_WARNING);NASL family Misc. NASL id VIRTUALBOX_5_1_30.NASL description The version of Oracle VM VirtualBox running on the remote host is 5.1.x prior to 5.1.30. It is, therefore, affected by multiple vulnerabilities as noted in the October 2017 Critical Patch Update advisory. Please consult the CVRF details for the applicable CVEs for additional information. Nessus has not tested for these issues but has instead relied only on the application last seen 2020-06-01 modified 2020-06-02 plugin id 103930 published 2017-10-18 reporter This script is Copyright (C) 2017-2019 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/103930 title Oracle VM VirtualBox 5.1.x < 5.1.30 (October 2017 CPU) NASL family FreeBSD Local Security Checks NASL id FREEBSD_PKG_1A802BA9F44411E69940B499BAEBFEAF.NASL description The OpenSSL project reports : Severity: High During a renegotiation handshake if the Encrypt-Then-Mac extension is negotiated where it was not in the original handshake (or vice-versa) then this can cause OpenSSL to crash (dependent on ciphersuite). Both clients and servers are affected. This issue does not affect OpenSSL version 1.0.2. last seen 2020-06-01 modified 2020-06-02 plugin id 97219 published 2017-02-17 reporter This script is Copyright (C) 2017-2018 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/97219 title FreeBSD : openssl -- crash on handshake (1a802ba9-f444-11e6-9940-b499baebfeaf)
References
- http://www.oracle.com/technetwork/security-advisory/cpujan2018-3236628.html
- http://www.oracle.com/technetwork/security-advisory/cpujan2018-3236628.html
- http://www.oracle.com/technetwork/security-advisory/cpuoct2017-3236626.html
- http://www.oracle.com/technetwork/security-advisory/cpuoct2017-3236626.html
- http://www.securityfocus.com/bid/96269
- http://www.securityfocus.com/bid/96269
- http://www.securitytracker.com/id/1037846
- http://www.securitytracker.com/id/1037846
- https://github.com/openssl/openssl/commit/4ad93618d26a3ea23d36ad5498ff4f59eff3a4d2
- https://github.com/openssl/openssl/commit/4ad93618d26a3ea23d36ad5498ff4f59eff3a4d2
- https://h20566.www2.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbgn03728en_us
- https://h20566.www2.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbgn03728en_us
- https://www.openssl.org/news/secadv/20170216.txt
- https://www.openssl.org/news/secadv/20170216.txt
- https://www.oracle.com/technetwork/security-advisory/cpuapr2019-5072813.html
- https://www.oracle.com/technetwork/security-advisory/cpuapr2019-5072813.html