CVE-2026-22750 Overview
A security misconfiguration vulnerability exists in Spring Cloud Gateway where SSL bundles configured via the spring.ssl.bundle configuration property are silently ignored. When administrators attempt to configure custom SSL certificates and trust stores, the framework falls back to default SSL configuration without any warning or error. This silent failure leaves applications vulnerable to using weaker or unintended SSL settings, potentially exposing sensitive communications to interception or tampering.
Critical Impact
Custom SSL bundle configurations are silently bypassed, resulting in applications using default SSL settings instead of intended security controls, potentially compromising encrypted communications integrity.
Affected Products
- Spring Cloud Gateway 4.2.0
- Spring Cloud Gateway versions prior to 4.2.x patch releases
- Spring Cloud Gateway versions prior to 5.0.2 and 5.1.1
Discovery Timeline
- 2026-04-10 - CVE CVE-2026-22750 published to NVD
- 2026-04-13 - Last updated in NVD database
Technical Details for CVE-2026-22750
Vulnerability Analysis
This vulnerability represents an External Control of System or Configuration Setting (CWE-15) flaw in Spring Cloud Gateway. The core issue lies in the framework's failure to properly process and apply SSL bundle configurations specified through the spring.ssl.bundle property.
When developers configure custom SSL bundles—typically to enforce specific certificate authorities, implement mutual TLS (mTLS), or use organization-specific certificates—Spring Cloud Gateway silently ignores these settings and reverts to its default SSL configuration. The dangerous aspect of this vulnerability is the absence of any warning or error message, leading administrators to believe their security configurations are in effect when they are not.
This misconfiguration bypass could result in:
- Applications communicating over less secure SSL/TLS configurations than intended
- Failure to enforce certificate pinning or custom trust chains
- Potential exposure to man-in-the-middle attacks if the default configuration is less restrictive
- Non-compliance with security policies requiring specific SSL configurations
Root Cause
The root cause stems from a defect in the SSL bundle configuration processing logic within Spring Cloud Gateway. The configuration property spring.ssl.bundle is parsed but not properly propagated to the underlying SSL context initialization. This results in the default SSL configuration being applied regardless of user-specified settings. The silent nature of this failure indicates a missing validation step that should verify whether custom configurations were successfully applied.
Attack Vector
This vulnerability is exploitable over the network without requiring authentication or user interaction. An attacker could potentially:
- Target Spring Cloud Gateway instances where administrators believe custom SSL configurations are enforced
- Exploit the gap between expected and actual SSL configuration to perform downgrade attacks
- Intercept or manipulate traffic that should have been protected by stricter SSL policies
- Bypass certificate validation requirements that were intended to be in place
The vulnerability affects the integrity of SSL/TLS communications rather than directly enabling data exfiltration or denial of service.
Detection Methods for CVE-2026-22750
Indicators of Compromise
- SSL/TLS connections using default certificates instead of configured custom certificates
- Missing custom certificate authority chains in TLS handshakes
- Gateway instances accepting connections that should be rejected by configured SSL policies
- Log entries indicating SSL bundle loading but no corresponding application of those bundles
Detection Strategies
- Review SSL/TLS handshake details for Spring Cloud Gateway endpoints to verify expected certificates are being presented
- Compare the actual SSL configuration in runtime against the intended spring.ssl.bundle settings
- Implement TLS fingerprinting to detect when default SSL configurations are in use
- Monitor for certificate mismatches between configured and observed certificates
Monitoring Recommendations
- Enable verbose SSL/TLS logging in Spring Cloud Gateway to track configuration loading
- Set up alerts for SSL configuration changes or initialization events
- Implement automated testing of SSL handshakes to verify custom certificates are in use
- Use certificate transparency logs to detect unexpected certificate usage
How to Mitigate CVE-2026-22750
Immediate Actions Required
- Upgrade Spring Cloud Gateway to version 5.0.2 or 5.1.1 (current supported open source releases)
- For enterprise customers on 4.2.x branch, contact VMware/Broadcom support for patched versions
- Manually verify that SSL configurations are being applied correctly after any configuration changes
- Review all Spring Cloud Gateway instances for custom SSL bundle configurations that may not be active
Patch Information
VMware has released patched versions of Spring Cloud Gateway to address this vulnerability. The recommended upgrade paths are:
- For open source users: Upgrade to Spring Cloud Gateway 5.0.2 or 5.1.1
- For 4.2.x users: Any release newer than 4.2.0 available on Maven Central addresses this issue
- For enterprise customers: Contact support for patches to the 4.2.x branch
Refer to the Spring Security Advisory CVE-2026-22750 for official guidance.
Workarounds
- Implement SSL/TLS termination at a reverse proxy or load balancer level instead of within Spring Cloud Gateway
- Use programmatic SSL configuration through Spring's WebClient customization instead of property-based configuration
- Deploy network-level controls to enforce SSL requirements independently of application configuration
- Implement runtime verification checks to confirm SSL bundles are properly loaded and applied
# Configuration verification example
# After deploying your Spring Cloud Gateway instance, verify SSL configuration
# by checking the actual certificate being presented
# Check the SSL certificate being served by your gateway
openssl s_client -connect your-gateway-host:443 -servername your-gateway-host 2>/dev/null | openssl x509 -noout -subject -issuer
# Compare the output against your expected custom certificate
# If default certificates are shown, the vulnerability may be affecting your deployment
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
