Spring BootFramework / library · VMware
CVE-2026-40973
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedA 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 authenticated users or deploy a gadget chain and execute code as the application's user. Affected: Spring Boot 4.0.0–4.0.5 (fix 4.0.6), 3.5.0–3.5.13 (fix 3.5.14), 3.4.0–3.4.15 (fix 3.4.16), 3.3.0–3.3.18 (fix 3.3.19), 2.7.0–2.7.32 (fix 2.7.33); predictable temp directory / `ApplicationTemp` ownership verification. Versions that are no longer supported are also affected per vendor advisory.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · high confidenceA local attacker on the same host can exploit Spring Boot's ApplicationTemp directory handling when server.servlet.session.persistent is enabled. The predictable temp directory allows the attacker to control the session storage location, enabling session hijacking and potentially code execution via gadget chains.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data
Spring BootFramework / library
< 2.7.33>= 3.3.0, < 3.3.19>= 3.4.0, < 3.4.16>= 3.5.0, < 3.5.14>= 4.0.0, < 4.0.6CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Local
- Complexity
- High
- Privileges
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
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Identify Spring Boot versionCheck the pom.xml for the spring-boot.version or run the application with --version flag, or inspect the spring-boot-autoconfigure JAR manifestAffected if The installed version is < 2.7.33, or >= 3.3.0 and < 3.3.19, or >= 3.4.0 and < 3.4.16, or >= 3.5.0 and < 3.5.14, or >= 4.0.0 and < 4.0.6
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Check if persistent sessions are enabledInspect the application.properties or application.yml file for the property server.servlet.session.persistent=true, or check if this property is set programmaticallyAffected if server.servlet.session.persistent is set to true, enabling the vulnerable temp directory behavior
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Locate the ApplicationTemp directoryCheck java.io.tmpdir system property at runtime, or inspect the Spring Boot actuator /env endpoint output for the temp directory configurationAffected if The temp directory is accessible to other local users or uses a predictable path pattern
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Verify temp directory permissionsRun 'ls -la' on the directory returned by java.io.tmpdir or the configured spring.boot.tmpdir, and check for world-writable or group-writable permissionsAffected if The temp directory has permissions allowing other local users to read, write, or modify files within it
A user is affected if they run a vulnerable Spring Boot version with persistent sessions enabled and their temp directory is accessible to other local users.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
dbcve · scoped2.7.333.3.193.4.16
Upgrade Spring Boot to fixed versions (4.0.6, 3.5.14, 3.4.16, 3.3.19, or 2.7.33). Alternatively, disable server.servlet.session.persistent and ensure strict filesystem permissions on temp directories.
Upgrade to 2.7.33, 3.3.19, 3.4.16, 3.5.14, or 4.0.6 depending on your current major.minor line
- Identify your current Spring Boot version from your pom.xml or build.gradle
- For Spring Boot 2.7.x line: upgrade to version 2.7.33
- For Spring Boot 3.3.x line: upgrade to version 3.3.19
- For Spring Boot 3.4.x line: upgrade to version 3.4.16
- For Spring Boot 3.5.x line: upgrade to version 3.5.14
- For Spring Boot 4.0.x line: upgrade to version 4.0.6
- Update the spring-boot.version property in your build configuration
- Run your build and verify the application starts successfully
Generated from the published advisory — verify against the referenced sources before acting.
Fix this in Spring Boot
Scoped from the published advisory
- Consultation2.0 h
- Implementation4.0 h
- Testing6.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,808.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-40973 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2026-40973 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Version or environment caveats, and links to real fixes
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