Apache Software Foundation · Apache Solr
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.
Public exploit code (PoC-in-GitHub) appeared 8 days after disclosure. No confirmed exploitation is recorded.
6 fixes in solr-parent over 21 months. The latest fix listed for solr-parent is 8.11.1.
No ATT&CK techniques are linked to this CVE yet. MITRE CTID has not mapped it, and no report passage in the corpus ties it to a technique.
Sigma rules © SigmaHQ, Detection Rule License 1.1; linked, not reproduced.
1 package in 1 ecosystem. Main package: org.apache.solr:solr-parent.
Upgrade to 8.8.2 or later
Fixes this CVE and 1 other known vulnerability in this package (CVE-2020-13957).
Set the version to 8.8.2 or later in your pom.xml or build.gradle.
The first fix for CVE-2021-27905.
| If you run | Upgrade to |
|---|---|
| All versions before 8.8.2 | 8.8.2 |
“Up to” means the second version is the fix and is not affected.
Pulses are indicator collections that anyone can publish. A mention is not confirmation of exploitation.