CVE-2016-1000027 is a critical-severity (CVSS 9.8) Deserialization of Untrusted Data vulnerability in org.springframework:spring-web. 4 public exploit or proof-of-concept references are indexed, so weaponization risk is real. A fix is available for org.springframework:spring-web — see the affected versions and patch details below.
Pivotal Spring Framework contains unsafe Java deserialization methods
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- 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-2016-1000027.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
org.springframework:spring-webReal-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
Pivotal Spring Framework before 6.0.0 suffers from a potential remote code execution (RCE) issue if used for Java deserialization of untrusted data. Depending on how the library is implemented within a product, this issue may or not occur, and authentication may be required.
Maintainers recommend investigating alternative components or a potential mitigating control. Version 4.2.6 and 3.2.17 contain enhanced documentation advising users to take precautions against unsafe Java deserialization, version 5.3.0 deprecate the impacted classes and version 6.0.0 removed it entirely.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.springframework:spring-web | all versions | 6.0.0org.springframework:spring-web:6.0.0 |
Affected Products
spring frameworkvmwareResearch use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.springframework:spring-web, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update org.springframework:spring-web to 6.0.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2016-1000027 is resolved across your whole dependency graph.
Workarounds
Do not deserialise data from untrusted sources: where the format allows it, restrict deserialisation to an explicit allowlist of expected types, and prefer a data-only format (JSON, Protobuf) over one that can reconstruct arbitrary objects until you can upgrade.
Frequently Asked Questions
Is CVE-2016-1000027 in your dependencies?
Find it across Maven, including transitive dependencies.