CVE-2025-49128 is a medium-severity (CVSS 4) CWE-209 vulnerability in com.fasterxml.jackson.core:jackson-core. A fix is available for com.fasterxml.jackson.core:jackson-core — see the affected versions and patch details below.
Jackson-core Vulnerable to Memory Disclosure via Source Snippet in JsonLocation
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.
Exploitation and automatability from CISA’s SSVC triage for CVE-2025-49128.
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-2025-49128 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 377,333 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-coreReal-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-core contains core low-level incremental ("streaming") parser and generator abstractions used by Jackson Data Processor. Starting in version 2.0.0 and prior to version 2.13.0, a flaw in jackson-core's JsonLocation._appendSourceDesc method allows up to 500 bytes of unintended memory content to be included in exception messages. When parsing JSON from a byte array with an offset and length, the exception message incorrectly reads from the beginning of the array instead of the logical payload start. This results in possible information disclosure in systems using pooled or reused buffers, like Netty or Vert.x. This issue was silently fixed in jackson-core version 2.13.0, released on September 30, 2021, via PR #652. All users should upgrade to version 2.13.0 or later. If upgrading is not immediately possible, applications can mitigate the issue by disabling exception message exposure to clients to avoid returning parsing exception messages in HTTP responses and/or disabling source inclusion in exceptions to prevent Jackson from embedding any source content in exception messages, avoiding leakage.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | com.fasterxml.jackson.core:jackson-core | ≥ 2.0.0&&< 2.13.0 | 2.13.0com.fasterxml.jackson.core:jackson-core:2.13.0 |
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-core, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update com.fasterxml.jackson.core:jackson-core to 2.13.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-49128 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-2025-49128 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2025-49128. 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-2025-49128 in your dependencies?
O3 Security finds CVE-2025-49128 across Maven dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.