CVE-2026-54515 is a medium-severity (CVSS 5.3) CWE-915 vulnerability in com.fasterxml.jackson.core:jackson-databind. O3 Security confirms whether CVE-2026-54515 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
jackson-databind: Case-insensitive deserialization bypasses per-property @JsonIgnoreProperties
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.
- 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-2026-54515.
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-2026-54515 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 369,023 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
com.fasterxml.jackson.core:jackson-databind☕tools.jackson.core:jackson-databind☕com.fasterxml.jackson.core:jackson-databind☕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
jackson-databind contains the general-purpose data-binding functionality and tree-model for Jackson Data Processor. From 2.8.0 until 2.18.9, 2.21.5, and 3.1.4, in BeanDeserializerBase.createContextual(), per-property @JsonIgnoreProperties exclusions are applied by _handleByNameInclusion(), producing a contextual deserializer whose BeanPropertyMap has the ignored properties removed. The subsequent per-property case-insensitivity block (triggered by @JsonFormat(ACCEPT_CASE_INSENSITIVE_PROPERTIES)) rebuilds from this._beanProperties (the original, unfiltered map) instead of contextual._beanProperties, then overwrites the filtered map — restoring every property _handleByNameInclusion had just removed. The ignored property becomes writable again. This vulnerability is fixed in 2.18.9, 2.21.5, and 3.1.4.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | com.fasterxml.jackson.core:jackson-databind | ≥ 3.1.0&&< 3.1.4 | 3.1.4 |
| ☕Maven | tools.jackson.core:jackson-databind | ≥ 3.1.0&&< 3.1.4 | 3.1.4 |
| ☕Maven | com.fasterxml.jackson.core:jackson-databind | ≥ 2.8.0&&< 2.18.9 | 2.18.9 |
| ☕Maven | com.fasterxml.jackson.core:jackson-databind | ≥ 2.19.0&&< 2.21.5 | 2.21.5 |
| ☕Maven | com.fasterxml.jackson.core:jackson-databind | ≥ 2.22.0&&< 2.22.1 | 2.22.1 |
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 3.1.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-54515 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-2026-54515 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-2026-54515. 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-2026-54515 in your dependencies?
O3 detects CVE-2026-54515 across Maven dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.