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TI-2021-09240 Aliases CVE-2021-27905GHSA-5phw-3jrp-3vj8

SSRF vulnerability with the Replication handler

Priority CRITICAL 86CWE-918Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 4 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA, GitHub and Red Hat.

Summary

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.

Why it matters now

EPSS 0.93053 99th percentileScored 2026-11-07
Fix Partial Apache Solr (Apache Software Foundation): 8.8.2org.apache.solr:solr-parent (Maven): 8.8.2Red Hat: 4 without a fix

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
ApacheApache SolrApache Solr to before 8.8.28.8.2Patch availableCNA
—org.apache.solr:solr-parent (Maven)before 8.8.28.8.2Patch availableGHSA-5phw-3jrp-3vj8
  • Apache Solr VendorApache Affected Apache Solr to before 8.8.2 Fixed in 8.8.2 Patch available CNA
  • org.apache.solr:solr-parent (Maven) Vendor— Affected before 8.8.2 Fixed in 8.8.2 Patch available GHSA-5phw-3jrp-3vj8

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:apache:solr:*:*:*:*:*:*:*:*before 8.8.2VulnerableApache
  • cpe:2.3:a:apache:solr:*:*:*:*:*:*:*:* Versions before 8.8.2 Vulnerable ·Apache

Remediation

  • Fix · CNA Apache Solr (Apache Software Foundation) Fixed in 8.8.2
  • Fix · GHSA-5phw-3jrp-3vj8 org.apache.solr:solr-parent (Maven) Fixed in 8.8.2 Advisory →

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    Apache Solr 8.8.2

    3 records Highest priority Priority CRITICAL 1 CRITICAL, 2 MEDIUM

    Other records, highest priority first

    • TI-2021-10560 Apache Solr Unprivileged users may be able to perform unauthorized read/write to collectionsPriority MEDIUM 47
    • TI-2021-10071 Misapplied Zookeeper ACLs can result in leakage of configured authentication and authorization settingsPriority MEDIUM 42
    Show all 3 records →

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat JBoss Data Virtualization 6AffectedNo fix planned: Out of support scope
Red Hat JBoss Enterprise Application Platform 6AffectedNo fix planned: Out of support scope
Red Hat JBoss Fuse 6AffectedNo fix planned: Out of support scope
Red Hat JBoss Fuse Service Works 6AffectedNo fix planned: Out of support scope
Not affected: 3 products
  • Red Hat Fuse 7
  • Red Hat Integration Camel K 1
  • Red Hat JBoss Web Server 3

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-27905
  2. 2026-10-03 Alias added: GHSA-5phw-3jrp-3vj8

References

Advisory 3

Other 21

  • TI-2024-30303 Apache Solr: Authentication bypass possible using a fake URL Path ending CVSS 3.1CRITICAL 9.8
  • TI-2019-13101 Injection in Apache Solr KEVCVSS 3.1HIGH 7.5
  • TI-2019-00170 Code injection in Apache Solr KEVCVSS 3.1HIGH 7.2
  • TI-2023-23979 The HTTP/2 protocol allows a denial of service (server resource consumption) because… KEVCVSS 3.1HIGH 7.5
  • TI-2017-09354 XML external entity injection in Apache Solr before 7.1 with Apache Lucene before 7.1 CVSS 3.1CRITICAL 9.8
  • TI-2020-10933 Incorrect authorization in Apache Solr CVSS 3.1CRITICAL 9.8
See all 46 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences