Summary
Apache Solr insecure inter-node communication
Full technical description
Apache Solr uses a PKI based mechanism to secure inter-node communication when security is enabled. It is possible to create a specially crafted node name that does not exist as part of the cluster and point it to a malicious node. This can trick the nodes in cluster to believe that the malicious node is a member of the cluster. So, if Solr users have enabled BasicAuth authentication mechanism using the BasicAuthPlugin or if the user has implemented a custom Authentication plugin, which does not implement either "HttpClientInterceptorPlugin" or "HttpClientBuilderPlugin", his/her servers are vulnerable to this attack. Users who only use SSL without basic authentication or those who use Kerberos are not affected.
Impact
The application does not adequately verify the identity of a user, device, or process before granting access. Typical impact: unauthorized access to functions or data reserved for authenticated parties.
CVE-2017-7660 has a CVSS score of 7.5 (High). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (5.5.5, 6.6.0); upgrading removes the vulnerable code path.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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org.apache.solr:solr-core to 5.5.5 or later; org.apache.solr:solr-core to 6.6.0 or later
Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.
Frequently Asked Questions
- What is CVE-2017-7660? CVE-2017-7660 is a high-severity improper authentication vulnerability in org.apache.solr:solr-core (maven), affecting versions >= 5.3.0, < 5.5.5. It is fixed in 5.5.5, 6.6.0. The application does not adequately verify the identity of a user, device, or process before granting access.
- How severe is CVE-2017-7660? CVE-2017-7660 has a CVSS score of 7.5 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
- Which versions of org.apache.solr:solr-core are affected by CVE-2017-7660? org.apache.solr:solr-core (maven) versions >= 5.3.0, < 5.5.5 is affected.
- Is there a fix for CVE-2017-7660? Yes. CVE-2017-7660 is fixed in 5.5.5, 6.6.0. Upgrade to this version or later.
- Is CVE-2017-7660 exploitable, and should I be worried? Whether CVE-2017-7660 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2017-7660 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2017-7660?
- Upgrade
org.apache.solr:solr-coreto 5.5.5 or later - Upgrade
org.apache.solr:solr-coreto 6.6.0 or later
- Upgrade