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CVE-2021-27905

SSRF vulnerability with the Replication handler

Published: Apr 13, 2021Updated: Nov 21, 2024 Sources: CVE List NVD GHSACWE-918
NVD MITRE
9.8CVSSCRITICAL
EPSS Score
93.1%
Top 0.2%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Am I actually vulnerable?1 Nuclei template available — see how to check your systems. How to verify

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.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:HI:HA:H
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:HConfidentiality
High
I:HIntegrity
High
A:HAvailability
High
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Weaknesses

CWE-918

Affected Products

Apache SolrApache Software Foundation
On-premWeb App
Web & CMS Plugins
org.apache.solr:solr-parentMavenOSS Libraries
solrapache
On-premWeb App
Web & CMS Plugins / cms-core
apache software foundationoss-projectUSWeb & CMS Pluginsaka apache foundation
mavenpackage-ecosystemOSS Libraries
apacheoss-projectUSWeb & CMS Pluginsaka apache http server, apache httpd

Attack Graph

Products CVE Techniques Tactics

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Exploitability

Official Patch Available
Workaround Available

MITRE ATT&CK

2 techniques
Command and Control
Initial Access
View detailed technique mapping

References

https://lists.apache.org/thread.html/r0ddc3a82bd7523b1453cb7a5e09eb5559517145425074a42eb326b10%40%3Cannounce.apache.org%3E
lists.apache.org
https://security.netapp.com/advisory/ntap-20210611-0009/
security.netapp.com
https://lists.apache.org/thread.html/r95df34bb158375948da82b4dfe9a1b5d528572d586584162f8f5aeef%40%3Cusers.solr.apache.org%3E
lists.apache.org
and 21 more references View all →

Timeline

Published
Apr 13, 2021
Last Updated
Nov 21, 2024

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