CVE-2026-40985
MEDIUMCVE-2026-40985 is a medium-severity (CVSS 6.4) Expression Language Injection vulnerability in org.springframework.webflow:spring-webflow. O3 Security confirms whether CVE-2026-40985 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Spring Web Flow has Data Binding Vulnerability with Unified EL Parser
Exploitation Status
No confirmed exploitation observed yet
- A successful exploit gives an attacker total control of the affected component, not partial access.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-40985.
Real-World Exposure
org.springframework.webflow:spring-webflow☕org.springframework.webflow:spring-webflow☕org.springframework.webflow:spring-webflowReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.
Description
Applications that configure the WebFlowELExpressionParser are vulnerable to the use of malicious Unified EL expressions.
Affected versions: Spring Web Flow 4.0.0; 3.0.0 through 3.0.1; 2.5.0 through 2.5.1.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.springframework.webflow:spring-webflow | ≥ 4.0.0&&< 4.0.1 | 4.0.1 |
| ☕Maven | org.springframework.webflow:spring-webflow | ≥ 3.0.0&&< 3.0.2 | 3.0.2 |
| ☕Maven | org.springframework.webflow:spring-webflow | all versions | No fix |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.springframework.webflow:spring-webflow. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update org.springframework.webflow:spring-webflow to 4.0.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-40985 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2026-40985 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-40985. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-40985 in your dependencies?
O3 detects CVE-2026-40985 across Maven dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.