PatchSiren cyber security CVE debrief
CVE-2026-40973 Spring CVE debrief
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 authenticated users or deploy a gadget chain and execute code as the application's user. The vulnerability exists in VMware Spring Boot versions 4.0.0–4.0.5, 3.5.0–3.5.13, 3.4.0–3.4.15, 3.3.0–3.3.18, and 2.7.0–2.7.32.
- Vendor
- Spring
- Product
- Spring Boot
- CVSS
- HIGH 7
- CISA KEV
- Not listed in stored evidence
- Original CVE published
- 2026-04-28
- Original CVE updated
- 2026-07-24
- Advisory published
- 2026-04-28
- Advisory updated
- 2026-07-24
Who should care
Users of VMware Spring Boot versions 4.0.0–4.0.5, 3.5.0–3.5.13, 3.4.0–3.4.15, 3.3.0–3.3.18, and 2.7.0–2.7.32 should be aware of this vulnerability and take steps to mitigate it. This includes operators, security teams, and platform administrators responsible for maintaining and securing these deployments.
Technical summary
The vulnerability exists in the `ApplicationTemp` directory used by VMware Spring Boot. A local attacker may be able to take control of this directory, allowing them to read session information and hijack authenticated users or execute code as the application's user. The vulnerability is particularly severe when `server.servlet.session.persistent` is set to `true` and the attack persists across application restarts. This issue affects multiple versions of VMware Spring Boot, including 4.0.0–4.0.5, 3.5.0–3.5.13, 3.4.0–3.4.15, 3.3.0–3.3.18, and 2.7.0–2.7.32.
Defensive priority
High
Recommended defensive actions
- Update to a fixed version of VMware Spring Boot: 4.0.6, 3.5.14, 3.4.16, 3.3.19, or 2.7.33
- Verify ownership of the temp directory used by `ApplicationTemp`
- Review and adjust the `server.servlet.session.persistent` setting
- Monitor for suspicious activity and implement compensating controls
- Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up
- Review compensating controls for exposed systems while remediation is scheduled and verified
- Track exceptions, retest remediated assets, and close the item only after evidence is documented
Evidence notes
The CVE record was published on 2026-04-28T00:16:24.357Z and was last modified on 2026-07-24T21:10:00.143Z. The NVD entry is currently Analyzed. Evidence is limited to public sources and may not reflect the full scope or impact of the vulnerability. Defenders should verify affected deployments and review official advisories for specific guidance.
Official resources
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CVE-2026-40973 CVE record
CVE.org
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CVE-2026-40973 NVD detail
NVD
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Source item URL
nvd_modified
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Mitigation or vendor reference
[email protected] - Vendor Advisory
AI-assisted PatchSiren debrief based on the supplied source corpus. The CVE record was published on 2026-04-28T00:16:24.357Z and has not been modified since then. The NVD entry is currently Analyzed.