CVE-2017-9803
Apache Solr's Kerberos plugin can be configured to use delegation tokens, which allows an application to reuse the authentication of an end-user or another application.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (2.19%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
Apache Solr's Kerberos plugin can be configured to use delegation tokens, which allows an application to reuse the authentication of an end-user or another application. There are two issues with this functionality (when using SecurityAwareZkACLProvider type of ACL provider e.g. SaslZkACLProvider). Firstly, access to the security configuration can be leaked to users other than the solr super user. Secondly, malicious users can exploit this leaked configuration for privilege escalation to further expose/modify private data and/or disrupt operations in the Solr cluster. The vulnerability is fixed from Apache Solr 6.6.1 onwards.
- CVSS 3.0
- 7.5 HIGHCVSS:3.0/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 2.19% probability · 82th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-287
- Affected
- apache/solr
- Source
- security@apache.org
EPSS 2.2% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- http://mail-archives.us.apache.org/mod_mbox/www-announce/201709.mbox/%3CCAOOKt53AOScg04zUh0%2BR_fcXD0C9s5mQ-OzdgYdnHz49u1KmXw%40mail.gmail.com%3E
- http://www.securityfocus.com/bid/100870Third Party Advisory, VDB Entry
- http://mail-archives.us.apache.org/mod_mbox/www-announce/201709.mbox/%3CCAOOKt53AOScg04zUh0%2BR_fcXD0C9s5mQ-OzdgYdnHz49u1KmXw%40mail.gmail.com%3E
- http://www.securityfocus.com/bid/100870Third Party Advisory, VDB Entry
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.