CVE-2016-2183

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Moderate Moderate Impact What does this mean?
7.5 CVSS v3 Base Score
4.3 CVSS v2 Base Score

Description

A flaw was found in the way the DES/3DES cipher was used as part of the TLS/SSL protocol. A man-in-the-middle attacker could use this flaw to recover some plaintext data by capturing large amounts of encrypted traffic between TLS/SSL server and client if the communication used a DES/3DES based ciphersuite.

Statement

OpenSSL security update RHSA-2016:1940 mitigates this issue by lowering priority of DES cipher suites so they are not preferred over cipher suites using AES. For compatibility reasons, DES cipher suites remain enabled by default and included in the set of cipher suites identified by the HIGH cipher string. Future updates may move them to MEDIUM or not enable them by default.

NSS addressed this issue by implementing limits on the amount of plain text which can be encrypted by using the same key. Once the limit is reached, the keys will need to be re-negotiated manually. This change will be available in nss-3.27.

GnuTLS is not affected by this issue, since it prioritizes AES before 3DES in the cipher list.

Mitigation

1.SSL/TLS configurations should prefer AES over DES. Versions of OpenSSL shipped with Red Hat Enterprise Linux 6 and 7 already do so. In the version of OpenSSL shipped with Red Hat Enterprise Linux 5, 3DES is listed below the AES-256 cipher and above the AES-128 cipher, therefore AES-256 based ciphersuite should not be disabled on the server.
2. Servers using OpenSSL, should not disable AES-128 and AES-256 ciphersuites. Versions of Apache shipped with Red Hat Enterprise Linux use the default cipher string, in which AES is preferred over DES/3DES based ciphersuites.

For JBoss Middleware, and Java mitigations, please review this knowledge base article:

https://access.redhat.com/articles/2598471

This can be mitigated on OpenShift Container Platform (OCP) by disabling the vulnerable TLS cipher suite in the applicable component. TLS configuration options for OCP are described here:

https://access.redhat.com/articles/5348961

Additional Information

External References

Content from www.cve.org is not included.https://www.cve.org/CVERecord?id=CVE-2016-2183

Content from nvd.nist.gov is not included.https://nvd.nist.gov/vuln/detail/CVE-2016-2183

https://access.redhat.com/articles/2548661

https://access.redhat.com/errata/RHSA-2016:1940

Content from sweet32.info is not included.https://sweet32.info/

Affected Packages and Issued Red Hat Security Errata

Products / Services Components State Errata
JBoss Core Services on RHEL 6 jbcs-httpd24-httpd Fixed RHSA-2017:2710
JBoss Core Services on RHEL 6 jbcs-httpd24-openssl Fixed RHSA-2017:2710
JBoss Core Services on RHEL 7 jbcs-httpd24-httpd Fixed RHSA-2017:2709
JBoss Core Services on RHEL 7 jbcs-httpd24-openssl Fixed RHSA-2017:2709
Red Hat Enterprise Linux 5 gnutls Not affected
Red Hat Enterprise Linux 5 nss Will not fix
Red Hat Enterprise Linux 5 openssl Will not fix
Red Hat Enterprise Linux 5 openssl097a Will not fix
Red Hat Enterprise Linux 5 Supplementary java-1.7.0-ibm Fixed RHSA-2017:0337
Red Hat Enterprise Linux 5 Supplementary java-1.6.0-ibm Fixed RHSA-2017:0338
Unless explicitly stated as not affected, all previous versions of packages in any minor update stream of a product listed here should be assumed vulnerable, although may not have been subject to full analysis.

Common Vulnerability Scoring System (CVSS) Score Details

Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authorities (CNA) source for its products and services (see Red Hat classifications ).

CVSS v3
CVSS v3 Score Breakdown Red Hat NVD
CVSS v3 Base Score 7.5 7.5
Attack Vector Network Network
Attack Complexity Low Low
Privileges Required None None
User Interaction None None
Scope Unchanged Unchanged
Confidentiality Impact High High
Integrity Impact None None
Availability Impact None None

CVSS v3 Vector

Red Hat CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

NVD CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

CVSS v2
CVSS v2 Score Breakdown Red Hat NVD
CVSS v2 Base Score 4.3 5
Attack Vector Network Network
Access Complexity Medium Low
Authentication None None
Confidentiality Impact Partial Partial
Integrity Impact None None
Availability Impact None None

CVSS v2 Vector

Red Hat AV:N/AC:M/Au:N/C:P/I:N/A:N

NVD AV:N/AC:L/Au:N/C:P/I:N/A:N

Acknowledgements

Red Hat would like to thank OpenVPN for reporting this issue. Upstream acknowledges Gaëtan Leurent (Inria) and Karthikeyan Bhargavan (Inria) as the original reporters.

Frequently Asked Questions

Why is Red Hat's CVSS v3 score or Impact different from other vendors?

 For open source software shipped by multiple vendors, the CVSS base scores may vary for each vendor's version depending on the version they ship, how they ship it, the platform, and even how the software is compiled. This makes scoring of vulnerabilities difficult for third-party vulnerability databases such as NVD that only provide a single CVSS base score for each vulnerability. Red Hat scores reflect how a vulnerability affects our products specifically.

For more information, see https://access.redhat.com/solutions/762393.

My product is listed as "Under investigation" or "Affected", when will Red Hat release a fix for this vulnerability?
  • "Under investigation" doesn't necessarily mean that the product is affected by this vulnerability. It only means that our Analysis Team is still working on determining whether the product is affected and how it is affected.
  • "Affected" means that our Analysis Team has determined that this product is affected by this vulnerability and might release a fix to address this in the near future.

What can I do if my product is listed as "Will not fix"?

 A "will not fix" status means that a fix for an affected product version is not planned or not possible due to complexity, which may create additional risk.

Available options depend mostly on the Impact of the vulnerability and the current Life Cycle phase of your product. Overall, you have the following options:
  • Upgrade to a supported product version that includes a fix for this vulnerability (recommended).
  • Apply a mitigation (if one exists).
  • Open a This content is not included.support case to request a prioritization of releasing a fix for this vulnerability.

What can I do if my product is listed as "Fix deferred"?

 A deferred status means that a fix for an affected product version is not guaranteed due to higher-priority development work.

Available options depend mostly on the Impact of the vulnerability and the current Life Cycle phase of your product. Overall, you have the following options:
  • Apply a mitigation (if one exists).
  • Open a This content is not included.support case to request a prioritization of releasing a fix for this vulnerability.
  • Red Hat Engineering focuses on addressing high-priority issues based on their complexity or limited lifecycle support. Therefore, lower-priority issues will not receive immediate fixes.

What is a mitigation?

 A mitigation is an action that can be taken to reduce the impact of a security vulnerability, without deploying any fixes.

I have a Red Hat product but it is not in the above list, is it affected?

 The listed products were found to include one or more of the components that this vulnerability affects. These products underwent a thorough evaluation to determine their affectedness by this vulnerability. Note that layered products (such as container-based offerings) that consume affected components from any of the products listed in this table may be affected and are not represented.

Why is my security scanner reporting my product as vulnerable to this vulnerability even though my product version is fixed or not affected?

 In order to maintain code stability and compatibility, Red Hat usually does not rebase packages to entirely new versions. Instead, we backport fixes and new features to an older version of the package we distribute. This can result in some security scanners that only consider the package version to report the package as vulnerable. To avoid this, we suggest that you use an approved vulnerability scanner from our This content is not included.Red Hat Vulnerability Scanner Certification program.