CVE-2021-20190
HIGHCVE-2021-20190 is a high-severity (CVSS 8.1) Deserialization of Untrusted Data vulnerability in com.fasterxml.jackson.core:jackson-databind. O3 Security confirms whether CVE-2021-20190 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Deserialization of untrusted data in jackson-databind
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-2021-20190.
Real-World Exposure
com.fasterxml.jackson.core:jackson-databind☕com.fasterxml.jackson.core:jackson-databindReal-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
A flaw was found in jackson-databind before 2.9.10.7. FasterXML mishandles the interaction between serialization gadgets and typing. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | com.fasterxml.jackson.core:jackson-databind | ≥ 2.7.0&&< 2.9.10.7 | 2.9.10.7 |
| ☕Maven | com.fasterxml.jackson.core:jackson-databind | all versions | 2.6.7.5 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for com.fasterxml.jackson.core:jackson-databind. 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 com.fasterxml.jackson.core:jackson-databind to 2.9.10.7 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-20190 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-2021-20190 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-2021-20190. 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.
The following Red Hat products do ship the vulnerable component, but do not enable the unsafe conditions needed to exploit, lowering their vulnerability impact: * JBoss Data Grid 7 * Business Process Management Suite 6 * Business Rules Management Suite 6 * JBoss Data Virtualization 6 * Red Hat Fuse Service Works 6 *…
Frequently Asked Questions
Is CVE-2021-20190 in your dependencies?
O3 detects CVE-2021-20190 across Maven dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.