CVE-2021-32824 — dubbo-parent
CRITICALCVE-2021-32824 is a critical-severity (CVSS 9.8) Deserialization of Untrusted Data vulnerability in org.apache.dubbo:dubbo-parent. 1 public exploit reference exists, so weaponization risk is real. A fix is available for org.apache.dubbo:dubbo-parent — see the affected versions and patch details below.
Apache Dubbo vulnerable to remote code execution via Telnet Handler
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
- 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.
Exploitation and automatability from CISA’s SSVC triage for CVE-2021-32824.
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-2021-32824 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 377,636 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.apache.dubbo:dubbo-parent☕org.apache.dubbo:dubbo-parentReal-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
Apache Dubbo is a java based, open source RPC framework. Versions prior to 2.6.10 and 2.7.10 are vulnerable to pre-auth remote code execution via arbitrary bean manipulation in the Telnet handler. The Dubbo main service port can be used to access a Telnet Handler which offers some basic methods to collect information about the providers and methods exposed by the service and it can even allow to shutdown the service. This endpoint is unprotected. Additionally, a provider method can be invoked using the invoke handler. This handler uses a safe version of FastJson to process the call arguments. However, the resulting list is later processed with PojoUtils.realize which can be used to instantiate arbitrary classes and invoke its setters. Even though FastJson is properly protected with a default blocklist, PojoUtils.realize is not, and an attacker can leverage that to achieve remote code execution. Versions 2.6.10 and 2.7.10 contain fixes for this issue.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.apache.dubbo:dubbo-parent | all versions | 2.6.10org.apache.dubbo:dubbo-parent:2.6.10 |
| ☕Maven | org.apache.dubbo:dubbo-parent | ≥ 2.7.0&&< 2.7.10 | 2.7.10org.apache.dubbo:dubbo-parent:2.7.10 |
Research 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.apache.dubbo:dubbo-parent, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update org.apache.dubbo:dubbo-parent to 2.6.10 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-32824 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-2021-32824 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2021-32824. 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-2021-32824 in your dependencies?
O3 Security finds CVE-2021-32824 across Maven dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.