vulnerability
Apache Solr: CVE-2021-27905: SSRF vulnerability with the Replication handler
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 7 | (AV:N/AC:L/Au:N/C:P/I:P/A:P) | Apr 13, 2021 | Nov 27, 2023 | Jul 3, 2025 |
Severity
7
CVSS
(AV:N/AC:L/Au:N/C:P/I:P/A:P)
Published
Apr 13, 2021
Added
Nov 27, 2023
Modified
Jul 3, 2025
Description
The ReplicationHandler (normally registered at "/replication" under a Solr core) in Apache Solr has a "masterUrl" (also "leaderUrl" alias) parameter that is used to designate another ReplicationHandler on another Solr core to replicate index data into the local core. To prevent a SSRF vulnerability, Solr ought to check these parameters against a similar configuration it uses for the "shards" parameter. Prior to this bug getting fixed, it did not. This problem affects essentially all Solr versions prior to it getting fixed in 8.8.2.
Solution
apache-solr-upgrade-latest
References
Rapid7 Labs
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