CVE-2026-40973: Spring Boot · Insecure Temporary File
Affects Spring BootSource CVE Database V5
Not known to be exploited · CVSS 7.0 High · fixed in 4.0.6 : patch Spring Boot soon.
Data as of 29 Oct 2026, 19:04 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 3% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 4.0.6, 3.5.14, 3.4.16 +2
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 27 Apr 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 29 Oct 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| SpringSpring Boot | Affected
| Fixed in
|
| SpringSpring Boot | Affected
| Fixed in
|
| SpringSpring Boot | Affected
| Fixed in
|
| SpringSpring Boot | Affected
| Fixed in
|
| SpringSpring Boot | Affected
| Fixed in
|
Mavenorg.springframework.boot/spring-bootpkg:maven/org.springframework.boot/spring-bootOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Official fixes are available in Spring Boot versions 4.0.6, 3.5.14, 3.4.16, 3.3.19, and 2.7.33. Users should upgrade to these or later versions to remediate the vulnerability. Since this is not a cloud service, patching the affected Spring Boot application versions is required. Patch status is confirmed by the vendor advisory. No additional mitigation steps are indicated beyond applying the official fixes.
Description
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. 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.