CVE-2026-40972
Timing Attack in Spring Boot DevTools Enables Remote Code Execution
Publication date: 2026-04-28
Last updated on: 2026-04-30
Assigner: VMware
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| vmware | spring_boot | From 4.0.0 (inc) to 4.0.6 (exc) |
| vmware | spring_boot | From 3.3.0 (inc) to 3.3.19 (exc) |
| vmware | spring_boot | From 3.4.0 (inc) to 3.4.16 (exc) |
| vmware | spring_boot | From 3.5.0 (inc) to 3.5.14 (exc) |
| vmware | spring_boot | to 2.7.33 (exc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-208 | Two separate operations in a product require different amounts of time to complete, in a way that is observable to an actor and reveals security-relevant information about the state of the product, such as whether a particular operation was successful or not. |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
CVE-2026-40972 is a high-severity vulnerability in Spring DevTools related to the remote secret comparison mechanism.
An attacker on the same network as the remote application can exploit a timing attack by measuring how long it takes to compare secrets.
This timing information can reveal details about the secret, and in extreme cases, the attacker can fully determine the secret.
With the secret, the attacker can upload modified classes to the remote application, potentially achieving remote code execution.
How can this vulnerability impact me? :
This vulnerability can have severe impacts including unauthorized remote code execution on the affected application.
An attacker who exploits this vulnerability can compromise the confidentiality, integrity, and availability of the application.
- Confidentiality impact: The attacker can discover sensitive secret information.
- Integrity impact: The attacker can upload and execute modified classes, altering application behavior.
- Availability impact: The attacker could disrupt the application by executing arbitrary code.
What immediate steps should I take to mitigate this vulnerability?
The immediate step to mitigate this vulnerability is to upgrade the affected Spring Boot versions to their respective fixed versions.
- Upgrade Spring Boot 4.0.x to version 4.0.6 or later.
- Upgrade Spring Boot 3.5.x to version 3.5.14 or later.
- Upgrade Spring Boot 3.4.x to version 3.4.16 or later (Enterprise Support Only).
- Upgrade Spring Boot 3.3.x to version 3.3.19 or later (Enterprise Support Only).
- Upgrade Spring Boot 2.7.x to version 2.7.33 or later (Enterprise Support Only).
No other mitigation steps are necessary beyond upgrading to these fixed versions.
How does this vulnerability affect compliance with common standards and regulations (like GDPR, HIPAA)?:
This vulnerability allows an attacker on the same network to potentially discover sensitive secrets through a timing attack, which in extreme cases can lead to remote code execution. Such unauthorized access and control over the application could result in exposure or manipulation of sensitive data.
Because of the high impact on confidentiality, integrity, and availability, this vulnerability could lead to non-compliance with data protection regulations like GDPR and HIPAA, which require safeguarding sensitive information and ensuring system integrity and availability.
Organizations using affected versions of Spring Boot should upgrade to fixed versions to mitigate this risk and maintain compliance with these standards.