CVE-2026-40971: spring spring boot Improper Certificate Validation
CVSS: 9.1v3.1CriticalAnalyzed
AliasesGHSA-9vc8-qppq-wvxc
Published 27-04-2026Last modified 28-04-2026
Vulnerability summary
CVE-2026-40971 is a critical (CVSS 9.1) Improper Certificate Validation vulnerability in spring spring boot. EPSS estimates a 0.30% chance of exploitation in the next 30 days, higher than 21.4% of scored vulnerabilities.
CVSS score
9.1/10
010
Critical · v3.1 (NVD)EPSS score
0.30%
0%100%
Low · +0.14 pp in 30 daysKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded
Timeline
- 27-04-2026PublishedVulnerability first disclosed.
- 28-04-2026Last modifiedVulnerability information updated.
Description
When configured to use an SSL bundle, Spring Boot's RabbitMQ auto-configuration does not perform hostname verification when connecting to the RabbitMQ broker. Affected: Spring Boot 4.0.0–4.0.5 (fix 4.0.6), 3.5.0–3.5.13 (fix 3.5.14) per vendor advisory.
CVSS metrics
3 scores · 3 sources · 1 versionCritical 9.1Preferred score · NVD (NIST)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:NSources3 sources · 5.0–9.1
- CVE.orgCNA5.0MediumCVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:LDiffers
- OSV · MavenEcosystem advisory · calculated5.0MediumCVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:LDiffers
EPSS trend
Probability
0.30%
Chance of exploitation in the next 30 days
Percentile
21%
Versus all other CVEs
30-day change
+0.14 pp
From 0.16% on 18-09-2026
18-09-202618-10-2026
EPSS score0.30%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Org.springframework.boot1 product
- spring-boot-rabbitmq≥ 4.0.0, < 4.0.6 | ≥ 3.5.0, < 3.5.14
Spring1 product
- spring boot≥ 4.0.0, < 4.0.6 | ≥ 3.5.0, < 3.5.14
Vmware1 product
- spring_boot≥ 3.5.0, < 3.5.14 | ≥ 4.0.0, < 4.0.6
3 vendors · 3 products
