CVE-2021-27905
Fixed in a distro release EPSS 93%
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.
Products: Apache Software Foundation Apache Solr
Fixed upstream
| Ecosystem | Package | Fixed in |
|---|---|---|
| Maven | org.apache.solr:solr-parent | 8.8.2 |
Distro releases
| Release | Package | Fixed in |
|---|---|---|
| Arch Linux | solr | 8.8.2-1 |
| Debian 12 | lucene-solr | 3.6.2+dfsg-23 |
| Debian 13 | lucene-solr | 3.6.2+dfsg-23 |
| Debian 14 | lucene-solr | 3.6.2+dfsg-23 |
| Ubuntu 20.04 LTS | lucene-solr | no fix |
| Ubuntu 22.04 LTS | lucene-solr | no fix |
| Ubuntu 24.04 LTS | lucene-solr | no fix |
| Ubuntu 25.10 | lucene-solr | no fix |
| Ubuntu 26.04 LTS | lucene-solr | no fix |
| Ubuntu 26.10 | lucene-solr | no fix |
| Ubuntu Pro 14.04 LTS | lucene-solr | no fix |
| Ubuntu Pro 16.04 LTS | lucene-solr | no fix |
| Ubuntu Pro 18.04 LTS | lucene-solr | no fix |