CVE-2026-40977
Spring Boot's PID file write follows symlinks at predictable default path
4.7
MEDIUM
CVSS 3.1
EPSS 0.02%
Description
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. 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); PID file / symlink behavior (`ApplicationPidFileWriter`). Versions that are no longer supported are also affected per vendor advisory.
How to fix CVE-2026-40977
To remediate CVE-2026-40977, upgrade the affected package to a fixed version below.
- —upgrade to 4.0.6 or later
Is CVE-2026-40977 being exploited?
Low — EPSS is 0.0%, meaning exploitation activity has not been observed at scale.
Affected packages (1)
- >= 4.0.0, < 4.0.6
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | MEDIUM4.7 | CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:L/A:H |