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SSL/TLS implementations accept export-grade RSA keys (FREAK attack)

Vulnerability Note VU#243585

Original Release Date: 2015-03-06 | Last Revised: 2015-10-27

Overview

Some implementations of SSL/TLS accept export-grade (512-bit or smaller) RSA keys even when not specifically requesting export grade ciphers. An attacker able to act as a Man-in-The-Middle (MiTM) could factor weak temporary RSA keys, obtain session keys, and decrypt SSL/TLS trafflc. This issue has been dubbed the "FREAK" (Factoring Attack on RSA-EXPORT Keys) attack.

Description

CWE-757: Selection of Less-Secure Algorithm During Negotiation ('Algorithm Downgrade')

CWE-326: Inadequate Encryption Strength

Some implementations of SSL/TLS accept export-grade (512-bit or smaller) RSA keys even when not specifically requesting export grade ciphers. This can occur when a MiTM attacker asks for export grade ciphers on behalf of a client, and the client insecurely accepts the export grade key. The attacker can then factor the weak RSA key and use this key to decrypt other data necessary to generate the session key. The attacker can then decrypt data in the session.

The researchers provide a more detailed explanation on their website.

Impact

The weak 512-bit "export grade" RSA keys can be factored to allow an attacker to decrypt information encrypted with these keys.

Solution

Update SSL/TLS libraries and applications

Vendors are currently working on patches to address this issue. Affected users are advised to check with the software vendor and update as soon as possible. The Vendor Status information below provides more information for each vendor.

Do not offer export grade ciphers

Configure server and client applications not to use export grade ciphers (EC).

Vendor Information

243585
 
Expand all

Apple Affected

Notified:  March 06, 2015 Updated: March 06, 2015

Status

Affected

Vendor Statement

We have not received a statement from the vendor.

Vendor Information

SecureTransport is affected.

Safari web browser is affected.

Google Affected

Notified:  March 06, 2015 Updated: March 06, 2015

Status

Affected

Vendor Statement

We have not received a statement from the vendor.

Vendor Information

BoringSSL versions before Nov 10, 2014 are vulnerable.

Google Chrome web browser prior to version 41 on various platforms are vulnerable.
Android Web Browser is vulnerable.

Microsoft Corporation Affected

Notified:  March 06, 2015 Updated: March 10, 2015

Status

Affected

Vendor Statement

We have not received a statement from the vendor.

Vendor Information

SChannel is vulnerable. Internet Explorer is also vulnerable.

A patch has been released. Please see the Microsoft Security Bulletin below.

Vendor References

NEC Corporation Affected

Updated:  October 26, 2015

Status

Affected

Vendor Statement

We provide information on this issue at the following URL <http://jpn.nec.com/security-info/secinfo/nv15-016.html>(only in Japanese)

Vendor Information

We are not aware of further vendor information regarding this vulnerability.

Vendor References

OpenSSL Affected

Notified:  March 06, 2015 Updated: March 06, 2015

Status

Affected

Vendor Statement

We have not received a statement from the vendor.

Vendor Information

OpenSSL versions before 1.0.1k are vulnerable. The vulnerability in OpenSSL is tracked as CVE-2015-0204.

Opera Affected

Updated:  March 06, 2015

Status

Affected

Vendor Statement

We have not received a statement from the vendor.

Vendor Information

Opera web browsers before Opera 28 on OSX and Android are vulnerable.

Research in Motion (RIM) Affected

Updated:  March 06, 2015

Status

Affected

Vendor Statement

We have not received a statement from the vendor.

Vendor Information

Blackberry Browser web browser is vulnerable.

Botan Not Affected

Notified:  March 06, 2015 Updated: March 06, 2015

Statement Date:   March 06, 2015

Status

Not Affected

Vendor Statement

We have not received a statement from the vendor.

Vendor Information

We are not aware of further vendor information regarding this vulnerability.

Cryptlib Not Affected

Notified:  March 06, 2015 Updated: March 09, 2015

Statement Date:   March 08, 2015

Status

Not Affected

Vendor Statement

We have not received a statement from the vendor.

Vendor Information

We are not aware of further vendor information regarding this vulnerability.

GnuTLS Not Affected

Notified:  March 06, 2015 Updated: March 06, 2015

Statement Date:   March 06, 2015

Status

Not Affected

Vendor Statement

We have not received a statement from the vendor.

Vendor Information

We are not aware of further vendor information regarding this vulnerability.

IAIK Java Group Not Affected

Notified:  March 06, 2015 Updated: March 17, 2015

Statement Date:   March 17, 2015

Status

Not Affected

Vendor Statement

We have not received a statement from the vendor.

Vendor Information

We are not aware of further vendor information regarding this vulnerability.

Legion of the Bouncy Castle Not Affected

Notified:  March 06, 2015 Updated: March 09, 2015

Statement Date:   March 09, 2015

Status

Not Affected

Vendor Statement

We have not received a statement from the vendor.

Vendor Information

We are not aware of further vendor information regarding this vulnerability.

Apache-SSL Unknown

Notified:  March 06, 2015 Updated: March 05, 2015

Status

Unknown

Vendor Statement

We have not received a statement from the vendor.

Vendor References

    Attachmate Unknown

    Notified:  March 06, 2015 Updated: March 05, 2015

    Status

    Unknown

    Vendor Statement

    We have not received a statement from the vendor.

    Vendor References

      Certicom Unknown

      Notified:  March 06, 2015 Updated: March 05, 2015

      Status

      Unknown

      Vendor Statement

      We have not received a statement from the vendor.

      Vendor References

        Crypto++ Library Unknown

        Notified:  March 06, 2015 Updated: March 05, 2015

        Status

        Unknown

        Vendor Statement

        We have not received a statement from the vendor.

        Vendor References

          EMC Corporation Unknown

          Notified:  March 06, 2015 Updated: March 05, 2015

          Status

          Unknown

          Vendor Statement

          We have not received a statement from the vendor.

          Vendor References

            Nettle Unknown

            Notified:  March 06, 2015 Updated: March 05, 2015

            Status

            Unknown

            Vendor Statement

            We have not received a statement from the vendor.

            Vendor References

              Oracle Corporation Unknown

              Notified:  March 06, 2015 Updated: March 05, 2015

              Status

              Unknown

              Vendor Statement

              We have not received a statement from the vendor.

              Vendor References

                PeerSec Networks Unknown

                Notified:  March 06, 2015 Updated: March 05, 2015

                Status

                Unknown

                Vendor Statement

                We have not received a statement from the vendor.

                Vendor References

                  SafeNet Unknown

                  Notified:  March 06, 2015 Updated: March 05, 2015

                  Status

                  Unknown

                  Vendor Statement

                  We have not received a statement from the vendor.

                  Vendor References

                    Spyrus Unknown

                    Notified:  March 06, 2015 Updated: March 05, 2015

                    Status

                    Unknown

                    Vendor Statement

                    We have not received a statement from the vendor.

                    Vendor References

                      libgcrypt Unknown

                      Notified:  March 06, 2015 Updated: March 05, 2015

                      Status

                      Unknown

                      Vendor Statement

                      We have not received a statement from the vendor.

                      Vendor References

                        mod_ssl Unknown

                        Notified:  March 06, 2015 Updated: March 05, 2015

                        Status

                        Unknown

                        Vendor Statement

                        We have not received a statement from the vendor.

                        Vendor References

                          wolfSSL Unknown

                          Notified:  March 06, 2015 Updated: March 05, 2015

                          Status

                          Unknown

                          Vendor Statement

                          We have not received a statement from the vendor.

                          Vendor References

                            View all 25 vendors View less vendors


                            CVSS Metrics

                            Group Score Vector
                            Base 7.8 AV:N/AC:L/Au:N/C:C/I:N/A:N
                            Temporal 6.4 E:F/RL:OF/RC:C
                            Environmental 6.4 CDP:ND/TD:H/CR:ND/IR:ND/AR:ND

                            References

                            Acknowledgements

                            This vulnerability was reported by researchers from INRIA, Microsoft Research, and IMDEA.

                            This document was written by Garret Wassermann.

                            Other Information

                            CVE IDs: None
                            Date Public: 2015-03-06
                            Date First Published: 2015-03-06
                            Date Last Updated: 2015-10-27 02:15 UTC
                            Document Revision: 25

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