This Week in Spring - May 19th, 2026

Hi Spring fans! Welcome to another installment of This Week in Spring!, this one written from the back of a taxi racing to the local Frankfurt train station, where I'll take a train to Munich for the amazing Kotlin Conf 2026 edition, where I'll be part of the keynote and deliver a talk on the...

Spring Office Hours Podcast: S5E16 - May Release Train Shift & What's Coming in Spring Boot 4.1

Join Dan Vega and DaShaun Carter for the latest updates from the Spring Ecosystem. In this episode, Dan and DaShaun break down the recently announced shift of the May release train from May 11-22 to June 1-5, and what that means for your upgrade planning across the Spring portfolio. They also dig...

A Bootiful Podcast: the legendary Adib Saikali

Hi, Spring fans! I'm so thrilled to have been able to sit down and talk to my friend Adib Saikali!...

This Week in Spring - May 12th, 2026

Hi, Spring fans! As I write this I am in Miami, FL at the CodeRemix.ai show, focused on the wide and wonderful world of OpenRewrite and Moderne. I've got a talk to give so let's dive right into it! a quick note about the upcoming release train dates in last week's installment of A Bootiful Podcas...

Spring Office Hours Podcast: S5E15 - Upgrading Spring and OSS Security

Join Dan Vega and DaShaun Carter for the latest updates from the Spring Ecosystem. In this episode, Dan and DaShaun tackle two challenges every Spring developer faces: keeping applications up to date and staying ahead of security vulnerabilities in open source dependencies. They explore how AI...

ChatMemory DEFAULT_CONVERSATION_ID causes unintended cross-user data leakage

Spring AI's chat memory component contained a problematic default that, when not explicitly overridden, could result in unintended data exposure between users...

Unbounded cache for function definitions

OOM error is possible while attempting to add infinite amount of functions to Function Registry...

Self Routing guard bypassed via function composition

Under infinite recursion in the routing layer, request-handling can cause OOM error...

Expression injection in MilvusVectorStore doDelete allows data destruction

Spring AI's MilvusVectorStoredoDeleteList implementation is vulnerable to filter-expression injection via unsanitized document IDs...

A Bootiful Podcast: Daniel Garnier-Moiroux on his new book 'Testing Spring Boot Applications'

Hi Spring fans! In this installment I'm thrilled to have had the opportunity to sit down and talk to Daniel Garnier-Moiroux and talk about "Testing Spring Boot Applications," from Manning! testing springboot java kotlin springframework...

Directory Traversal with spring-cloud-config-server

Spring Cloud Config allows applications to server arbitrary text and binary files through the spring-cloud-config-server module. A malicious user, or attacker, can send a request using a specially crafted URL that can lead to a directory traversal attack...

Spring Cloud Config Server Logged Sensitive Information

When enabling trace logging in Spring Cloud Config Server sensitive information was placed in plain text in the logs...

Spring Cloud Config Clients Can Access Secrets From Any Project The Config Server Has Access To On Google Secrets Manager

When using Google Secrets Manager as a backend for the Spring Cloud Config server a client can craft a request to the config server potentially exposing secrets from unintended GCP projects...

This Week in Spring - May 5th, 2026

Hi, Spring fans! Welcome to another installment of This Week in Spring! It's May 5th, 2026, and I'm in Mainz, Germany, for the legendary JAX conference! It's been infinitely far too long since I've been at this amazing show, and I'm oh-so happy to be back here! Tonight, after my two talks here, I...

Spring Office Hours Podcast: S5E14 - Spec Driven Development with Simon Martinelli

Join Dan Vega and DaShaun Carter for the latest updates from the Spring Ecosystem. In this episode, Dan and DaShaun are joined by Java Champion, Vaadin Champion, and Oracle ACE Pro Simon Martinelli to talk about Spec-Driven Development. With AI reshaping how we write code, Simon makes the case th...

Ronald Dehuysser, founder of JobRunr, on their ambitious new JavaClaw-like agent runtime

Hi Spring fans! In this installment, I talk to my friend and JobRunr founder Ronald Dehuysser about the latest and greatest, and their new "JavaClaw" project!...

Spring gRPC SecurityContext leaks across requests on authorization failure

When an authenticated user is denied access to a gRPC method, their authenticated identity remains bound to the gRPC worker thread and can be inherited by a subsequent unauthenticated request on the same thread. This may allow the subsequent user to gain escalated permissions...

Spring gRPC AuthenticationException message reflected to remote client

The raw message of every server-side AuthenticationException is returned to the unauthenticated remote caller in the gRPC status description. This allows an attacker to obtain information about the authentication failure, which may be useful for further attacks...

This Week in Spring - April 28th, 2026

Hi Spring fans! Welcome to another installment of This Week in Spring! As I write this, I'm on PTO in beautiful Santorini, Greece, catching up on some news and about to cruise the islands for some sightseeing. There's nothing quite like springtime in the Mediterranean! I couldn't dream of enjoyin...

VectorStore FilterExpression Converter injection

In Spring AI, various FilterExpressionConverter implementations accept a filter expression object and translate them to specific vector store query languages. In several cases, keys and values are not properly escaped, leading to the ability to alter the query. Only applications that use...

ONNX model cache defaults to world-writable predictable /tmp directory

In Spring AI, having access to a shared environment can expose the ONNX model used by the application. Only applications that use TransformersEmbeddingModel and have the cache enabled, using the default location, are affected...

VectorStoreChatMemoryAdvisor conversation scoping can lead to cross-tenant memory exfiltration

In Spring AI, an attacker can bypass conversation isolation and exfiltrate sensitive memory from other users’ chat histories, including secrets and credentials, by injecting filter logic through conversationId . Only applications that use VectorStoreChatMemoryAdvisor and pass user-supplied input ...

OOM by attacker-controlled PDF

In Spring AI, a malicious PDF file can be crafted that triggers the allocation of unreasonable amounts of memory when handled by ForkPDFLayoutTextStripper . Only applications that use ForkPDFLayoutTextStripper and pass user-supplied input to DocumentReader s are affected...

SQL Injection in CosmosDBVectorStore.doDelete()

SQL injection vulnerability in Spring AI's CosmosDBVectorStore allows attackers to execute arbitrary SQL queries via crafted document IDs. Only applications that use CosmosDBVectorStore and pass user-supplied input as document ids are affected...

Elasticsearch auto-configuration with an SSL bundle disables TLS hostname verification

When configured to use an SSL bundle, Spring Boot's Elasticsearch auto-configuration does not perform hostname verification when connecting to the Elasticsearch server...

DevTools remote secret comparison is vulnerable to timing attacks

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. In extreme circumstances this could result in the attacker determining the secret and uploading changed classes, thereby achieving remote code executio...

RabbitMQ auto-configuration with an SSL bundle disables TLS hostname verification

When configured to use an SSL bundle, Spring Boot's RabbitMQ auto-configuration does not perform hostname verification when connecting to the RabbitMQ broker...

Random value property source uses a weak PRNG unsuitable for secrets

Values produced by $random.value are not suitable for use as secrets. $random.uuid is not affected. $random.int and $random.long should never be used for secrets as they are numeric values with a predictable range...

Cassandra SSL auto-configuration disables TLS hostname verification

Spring Boot's Cassandra auto-configuration does not perform hostname verification when establishing an SSL connection to Cassandra...

A Bootiful Podcast: A Bootiful Podcast: Dr. Venkat Subramaniam and James Ward on Intelligent Kotlin and So Much More

I am beyond thrilled that I got to co-present with two legends, Dr. Venkat Subramaniam and James Ward, at Voxxed Days Amsterdam, and even more so that they both sat down for a quick discussion with me right before that presentation. Enjoy!...

PID file write follows symlinks at predictable default path

When an application is configured to use ApplicationPidFileWriter , a local attacker with write access to the PID file's location can corrupt one file on the host each time the application is started...

Predictable temp directory accepted without ownership verification

A local attacker on the same host as the application may be able to take control of the directory used by ApplicationTemp . When server.servlet.session.persistent is set to true and the attack persists across application restarts, this may allow the attacker to read session information and hijack...

Default security filter chain has no authorization rule with Actuator but without Health

In certain circumstances, Spring Boot's default web security is ineffective allowing unauthorized access to all endpoints. For an application to be vulnerable, it must: If any of the above does not apply, the application is not vulnerable...

Spring Security Authorization Server Dynamic Client Registration endpoints perform insufficient validation of client metadata

Spring Security Authorization Server Dynamic Client Registration endpoints perform insufficient validation of certain client metadata fields when explicitly enabled. An attacker possessing a valid Initial Access Token can dynamically register a malicious client with crafted metadata. Depending on...

This Week in Spring - April 21st, 2026

Hi Spring fans! Welcome to another installment of This Week in Spring! What a week it's been since we last talked. I was in Barcelona, Spain, for the amazing Spring I/O event there. It has become my favorite show, full stop. Just such an amazing experience. So many wonderful things going on there...

Spring Security JdbcOneTimeTokenService allows a one-time token to authenticate multiple sessions

Applications that explicitly configure One-Time Token login with JdbcOneTimeTokenService are vulnerable to a Time-of-check Time-of-use TOCTOU race condition. An attacker with a valid one-time token can send concurrent requests to the authentication endpoint, allowing the single-use token to be...

Servlet Path Not Correctly Included in Path Matching of XML Authorization Rules

If an application uses to define the servlet path for computing a path matcher, then the servlet path is not included and the related authorization rules are not exercised. This can lead to an authorization bypass...

Potential Security Misconfiguration when Using withIssuerLocation

When an application configures JWT decoding with NimbusJwtDecoder or NimbusReactiveJwtDecoder , it must configure an OAuth2TokenValidator separately, for example by calling setJwtValidator . This is easy to miss when using NimbusJwtDecoderwithIssuerLocation or...

Spring Office Hours Podcast: S5E13 - Community Potluck

Join Dan Vega and DaShaun Carter for the latest updates from the Spring Ecosystem. In this Potluck episode, Dan and DaShaun open up the floor to the community, answering your questions on Spring Boot, Spring AI, Spring Security, and whatever else is on your mind. Potluck episodes are shaped...

Unauthorized User Impersonation when Using X.509 Client Certificates

SubjectX500PrincipalExtractor does not correctly handle certain malformed X.509 certificate CN values, which can lead to reading the wrong value for the username. In a carefully crafted certificate, this can lead to an attacker impersonating another user...

User Attribute Enumeration when Using DaoAuthenticationProvider

If an application is using the UserDetailsisEnabled , isAccountNonExpired , or isAccountNonLocked user attributes, to enable, expire, or lock users, then DaoAuthenticationProvider 's timing attack defense can be bypassed for users who are disabled, expired, or locked...

Servlet Path Not Correctly Included in Path Matching of HttpSecurity#securityMatchers

If an application is using securityMatchersString and a PathPatternRequestMatcher.Builder bean to prepend a servlet path, matching requests to that filter chain may fail and its related security components will not be exercised as intended by the application. This can lead to the authentication,...

Denial of service in static resource handling on Windows platforms

Spring MVC and WebFlux applications are vulnerable to Denial of Service attacks when resolving static resources. More precisely, an application can be vulnerable when all the following are true: When all the conditions above are met, the attacker can send malicious requests that are slow to resol...

Static resource cache poisoning in Spring MVC and WebFlux

Spring MVC and WebFlux applications are vulnerable to cache poisoning when resolving static resources. More precisely, an application can be vulnerable when all the following are true: When all the conditions above are met, the attacker can send malicious requests and poison the resource cache wi...

Spring Framework DoS with Multipart Temp Files in WebFlux

A WebFlux server application that processes multipart requests creates temp files for parts larger than 10 K. Under some circumstances, temp files may remain not deleted after the request is fully processed. This allows an attacker to consume available disk space...

A Bootiful Podcast: the legendary Craig Walls

Hi Spring fans! In this installment we talk to the legendary Craig Walls, author of Spring In Action , Spring AI in Action , and more!...

Spring AI Agentic Patterns (Part 7): Session API — Event-Sourced Short-Term Memory with Context Compaction

A New Session API for Spring AI — Structured, Compactable, Multi-Agent-Ready Part 7 of theSpring AI Agentic Patterns series completes the memory picture. After covering Agent Skills, AskUserQuestionTool, TodoWriteTool, Subagent Orchestration, A2A Integration, and AutoMemoryTools for long-term...

This Week in Spring - April 14th, 2026

Hi, Spring fans! ¡Hola from Barcelona, Spain! I'm at the amazing Spring I/O event, hanging out with some of the amazing Spring ecosystem developers! Life is amazing here in the warm sun of springtime. There's a lot to look at this week, so let's dive right into it! Another nice tutorial on how to...

Spring Office Hours Podcast: S5E12 - Developer Soft Skills with Arun Gupta

Join Dan Vega and DaShaun Carter for another essential update from the Spring ecosystem. In this episode, the guys are joined by DevRel and Java legend Arun Gupta to discuss a topic often overlooked but vital for career longevity: soft skills for developers. Drawing from his decades of experience...

SSL bundle configuration silently bypassed in Spring Cloud Gateway

When configuring SSL bundles in Spring Cloud Gateway by using the configuration property spring.ssl.bundle , the configuration was silently ignored and the default SSL configuration was used instead...