CVE-2023-20861 is a medium-severity (CVSS 6.5) Uncontrolled Resource Consumption vulnerability in org.springframework:spring-expression. A fix is available for org.springframework:spring-expression — see the affected versions and patch details below.
Spring Framework vulnerable to denial of service via specially crafted SpEL expression
Exploitation Status
No confirmed exploitation observed yet
- 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-2023-20861.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2023-20861 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 378,567 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
org.springframework:spring-expression☕org.springframework:spring-expression☕org.springframework:spring-expressionReal-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
In Spring Framework versions 6.0.0 - 6.0.6, 5.3.0 - 5.3.25, 5.2.0.RELEASE - 5.2.22.RELEASE, and older unsupported versions, it is possible for a user to provide a specially crafted SpEL expression that may cause a denial-of-service (DoS) condition.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.springframework:spring-expression | ≥ 6.0.0&&< 6.0.7 | 6.0.7org.springframework:spring-expression:6.0.7 |
| ☕Maven | org.springframework:spring-expression | ≥ 5.3.0&&< 5.3.26 | 5.3.26org.springframework:spring-expression:5.3.26 |
| ☕Maven | org.springframework:spring-expression | all versions | 5.2.23.RELEASEorg.springframework:spring-expression:5.2.23.RELEASE |
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-expression, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update org.springframework:spring-expression to 6.0.7 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-20861 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 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2023-20861 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2023-20861. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
| Product | Fixed in | Advisory |
|---|---|---|
| AMQ Broker 7.10.3 | see advisory | RHSA-2023:3185 |
| OCP-Tools-4.12-RHEL-8 | jenkins-0:2.401.1.1686649641-3.el8 | RHSA-2023:3610 |
| OCP-Tools-4.12-RHEL-8 | jenkins-0:2.426.3.1706515686-3.el8 | RHSA-2024:0778 |
| OCP-Tools-4.13-RHEL-8 | jenkins-0:2.401.1.1686680404-3.el8 | RHSA-2023:3622 |
| Red Hat Fuse 7.12 | springframework | RHSA-2023:3954 |
| Red Hat support for Spring Boot 2.7.13 | springframework | RHSA-2023:4612 |
| Red Hat Virtualization Engine 4.4 | ovirt-dependencies-0:4.5.3-1.el8ev | RHSA-2023:3771 |
| RHINT Camel-Springboot 3.20.1 | springframework | RHSA-2023:2100 |
Frequently Asked Questions
Is CVE-2023-20861 in your dependencies?
O3 Security finds CVE-2023-20861 across Maven dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.