CVE-2025-49128 Jackson-core Vulnerable to Memory Disclosure via Source Snippet in JsonLocation
Attackers can read up to 500 bytes of unintended memory content via JSON parsing exception messages in Jackson-core, potentially exposing sensitive data from reused buffers.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2025-49128?
CVE-2025-49128 is a medium-severity vulnerability in FasterXML jackson-core, published on 6 Jun 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Official 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.
Weakness: CWE-209
Which versions are affected by CVE-2025-49128?
2 open source packages ship an affected version, including com.fasterxml.jackson.core:jackson-core.
| Package | Affected | Fixed in |
|---|---|---|
com.fasterxml.jackson.core:jackson-core Maven | From 2.0.0 | 2.13.0 |
com.fasterxml.jackson.core:jackson-core Maven | From 2.0.0 | 2.13.0 |
How do I fix CVE-2025-49128?
Upgrade com.fasterxml.jackson.core:jackson-core to 2.13.0 or later.
Is CVE-2025-49128 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-49128 exists.
Sources
Also known as CLEANSTART-2026-GA95827, CLEANSTART-2026-LD22950, CLEANSTART-2026-OC06333, DEBIAN-CVE-2025-49128, ECHO-ca28-4475-76f1, GHSA-wf8f-6423-gfxg and 11 more.