CVE-2017-3732: BN_mod_exp may produce incorrect results on x86_64
As noted by the OpenSSL team, the likelihood of being able to craft a practical attack that uses this flaw is very low. In addition, Node.js enables SSLOPSINGLEDHUSE, further decreasing the chance of a successful exploit of this vulnerability in a Node.js service.
All active versions of Node.js are affected, but the severity is very low for Node.js users.
Other sources
There is a carry propagating bug in the x8664 Montgomery squaring procedure in OpenSSL 1.0.2 before 1.0.2k and 1.1.0 before 1.1.0d. No EC algorithms are affected. Analysis suggests that attacks against RSA and DSA as a result of this defect would be very difficult to perform and are not believed likely. Attacks against DH are considered just feasible (although very difficult) because most of the work necessary to deduce information about a private key may be performed offline. The amount of resources required for such an attack would be very significant and likely only accessible to a limited number of attackers. An attacker would additionally need online access to an unpatched system using the target private key in a scenario with persistent DH parameters and a private key that is shared between multiple clients. For example this can occur by default in OpenSSL DHE based SSL/TLS ciphersuites. Note: This issue is very similar to CVE-2015-3193 but must be treated as a separate problem.
There is a carry propagating bug in the x8664 Montgomery squaring procedure. No EC algorithms are affected. Analysis suggests that attacks against RSA and DSA as a result of this defect would be very difficult to perform and are not believed likely. Attacks against DH are considered just feasible (although very difficult) because most of the work necessary to deduce information about a private key may be performed offline. The amount of resources required for such an attack would be very significant and likely only accessible to a limited number of attackers. An attacker would additionally need online access to an unpatched system using the target private key in a scenario with persistent DH parameters and a private key that is shared between multiple clients. For example this can occur by default in OpenSSL DHE based SSL/TLS ciphersuites.
Note: This issue is very similar to CVE-2015-3193 but must be treated as a separate problem.
OpenSSL 1.0.2 users should upgrade to 1.0.2k
External References:
https://www.openssl.org/news/secadv/20170126.txt
— Red Hat
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
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redhat/jbcs-httpd24-apache-commons-daemonto a version that resolves this vulnerability.Fixed in 0:1.1.0-1.redhat_2.1.jbcs.el6 - Upgrade
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redhat/jbcs-httpd24-apache-commons-daemon-jsvcto a version that resolves this vulnerability.Fixed in 1:1.1.0-1.redhat_2.jbcs.el6 - Upgrade
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redhat/jbcs-httpd24-aprto a version that resolves this vulnerability.Fixed in 0:1.6.3-14.jbcs.el6 - Upgrade
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redhat/jbcs-httpd24-apr-utilto a version that resolves this vulnerability.Fixed in 0:1.6.1-9.jbcs.el6 - Upgrade
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redhat/jbcs-httpd24-httpdto a version that resolves this vulnerability.Fixed in 0:2.4.29-17.jbcs.el6 - Upgrade
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redhat/jbcs-httpd24-nghttp2to a version that resolves this vulnerability.Fixed in 0:1.29.0-8.jbcs.el6 - Upgrade
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redhat/jbcs-httpd24-opensslto a version that resolves this vulnerability.Fixed in 1:1.0.2n-11.jbcs.el6 - Upgrade
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redhat/jbcs-httpd24-apache-commons-daemonto a version that resolves this vulnerability.Fixed in 0:1.1.0-1.redhat_2.1.jbcs.el7 - Upgrade
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redhat/jbcs-httpd24-apache-commons-daemon-jsvcto a version that resolves this vulnerability.Fixed in 1:1.1.0-1.redhat_2.jbcs.el7 - Upgrade
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redhat/jbcs-httpd24-aprto a version that resolves this vulnerability.Fixed in 0:1.6.3-14.jbcs.el7 - Upgrade
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redhat/jbcs-httpd24-apr-utilto a version that resolves this vulnerability.Fixed in 0:1.6.1-9.jbcs.el7 - Upgrade
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redhat/jbcs-httpd24-httpdto a version that resolves this vulnerability.Fixed in 0:2.4.29-17.jbcs.el7 - Upgrade
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redhat/jbcs-httpd24-nghttp2to a version that resolves this vulnerability.Fixed in 0:1.29.0-8.jbcs.el7 - Upgrade
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redhat/jbcs-httpd24-opensslto a version that resolves this vulnerability.Fixed in 1:1.0.2n-11.jbcs.el7 - Upgrade
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redhat/javato a version that resolves this vulnerability.Fixed in 1.8.0-ibm-1:1.8.0.5.20-1jpp.1.el6_10 - Upgrade
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redhat/javato a version that resolves this vulnerability.Fixed in 1.8.0-ibm-1:1.8.0.5.20-1jpp.1.el7 - Upgrade
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debian/opensslto a version that resolves this vulnerability.Fixed in 1.1.1w-0+deb11u1Fixed in 1.1.1w-0+deb11u2Fixed in 3.0.15-1~deb12u1Fixed in 3.0.14-1~deb12u2Fixed in 3.4.1-1 - Upgrade
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redhat/opensslto a version that resolves this vulnerability.Fixed in 1.0.2 - Upgrade
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redhat/opensslto a version that resolves this vulnerability.Fixed in 1.1.0 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 4.7.3Fixed in 6.9.5Fixed in 7.5.0 - Upgrade
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OpenSSLto a version that resolves this vulnerability.Fixed in 1.0.2k
Event History
Parent advisories
This vulnerability appears in the following advisories.
Frequently Asked Questions
What is the severity of CVE-2017-3732?
CVE-2017-3732 is considered to have low severity due to its complex exploitation requirements.
How do I fix CVE-2017-3732?
You can fix CVE-2017-3732 by upgrading to OpenSSL version 1.0.2k or 1.1.0d or later.
Which software is affected by CVE-2017-3732?
CVE-2017-3732 affects OpenSSL versions prior to 1.0.2k and 1.1.0d.
Does CVE-2017-3732 affect EC algorithms?
No, CVE-2017-3732 does not affect EC (Elliptic Curve) algorithms.
What types of attacks could CVE-2017-3732 enable?
CVE-2017-3732 may potentially enable difficult-to-execute attacks against RSA and DSA, but practical exploitation is challenging.