Medium severity · published Apr 27, 2026
CVE-2026-40970
When configured to use an SSL bundle, Spring Boot's Elasticsearch auto-configuration does not perform hostname verification when connecting to the Elasticsearch server
6.8
CVSS
0.1%
EPSS
No
On KEV
Description
When configured to use an SSL bundle, Spring Boot's Elasticsearch auto-configuration does not perform hostname verification when connecting to the Elasticsearch server.
Affected: Spring Boot 4.0.0–4.0.5; upgrade to 4.0.6 or later per vendor advisory.
CVSS vector
CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
Attack vector
Adjacent
Complexity
High
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.1% · higher than 3% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
SB
Spring Boot · Spring
4.0.0 before 4.0.6 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-40970
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-40970
Vendor Advisory
https://spring.io/security/cve-2026-40970
More from Spring Boot
9.8
CVE-2026-40974
Spring Boot's Cassandra auto-configuration does not perform hostname verification when establishing an SSL connection to Cassandra
9.1
CVE-2026-40976
In certain circumstances, Spring Boot's default web security is ineffective allowing unauthorized access to all endpoints
9.1
CVE-2026-40971
When configured to use an SSL bundle, Spring Boot's RabbitMQ auto-configuration does not perform hostname verification when connecting to the RabbitMQ broker
7.5
CVE-2026-40975
Values produced by ${random.value} are not suitable for use as secrets
7.5
CVE-2026-40972
An attacker on the same network as the remote application may be able to utilize a timing attack to discover information about the remote secret