Critical severity · published Apr 13, 2021
CVE-2021-27905
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…
9.8
CVSS
93.1%
EPSS
No
On KEV
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
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)93.1% · higher than 100% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
SO
Solr · Apache
before 8.8.2 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-27905
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-27905
Mailing List
https://lists.apache.org/thread.html/r0ddc3a82bd7523b1453cb7a5e09eb5559517145425074a42eb326b10%40%3Cannounce.apache.org%3E
lists.apache.org
https://lists.apache.org/thread.html/r140128dc6bb4f4e0b6a39e962c7ca25a8cbc8e48ed766176c931fccc%40%3Cusers.solr.apache.org%3E
lists.apache.org
https://lists.apache.org/thread.html/r3da74965aba2b5f5744b7289ad447306eeb2940c872801819faa9314%40%3Cusers.solr.apache.org%3E
lists.apache.org
https://lists.apache.org/thread.html/r6ccec7fc54d82591b23c143f1f6a6e38f6e03e75db70870e4cb14a1a%40%3Ccommits.ofbiz.apache.org%3E
lists.apache.org
https://lists.apache.org/thread.html/r720a4a0497fc90bad5feec8aa18b777912ee15c7eeb5f882adbf523e%40%3Ccommits.ofbiz.apache.org%3E
lists.apache.org
https://lists.apache.org/thread.html/r78a3a4f1138a1608b0c6d4a2ee7647848c1a20b0d5c652cd9b02c25a%40%3Ccommits.ofbiz.apache.org%3E
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