cve.bz

CVE-2021-27905

9.8 criticalEPSS 93%

Critical (9.8) in apache solr. EPSS 93% chance of exploitation in the next 30 days. Fixed in org.apache.solr:solr-parent 8.8.2.

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.

Severity

CVSS 3.1

9.8 critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
93% chance of exploitation in the next 30 days; higher than 99% of CVEs (scores of 2026-10-31)
CWE
CWE-918
Published
Modified
Record from
the NVD, synced

Affected

Packages (OSV)

AdvisoryEcosystemPackageAffectedFixed in
GHSA-5phw-3jrp-3vj8Mavenorg.apache.solr:solr-parent<8.8.28.8.2

References

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