What is CVE-2026-54518?

CVE-2026-54518 is a medium-severity incorrect authorization vulnerability in com.fasterxml.jackson.core:jackson-databind (maven), affecting versions >= 2.21.0, < 2.21.4. It is fixed in 2.21.4, 3.1.4. The application does not correctly enforce access controls, allowing a principal to access resources or operations beyond their granted permissions.

How severe is CVE-2026-54518?

CVE-2026-54518 has a CVSS score of 6.5 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.

Which packages are affected by CVE-2026-54518?

com.fasterxml.jackson.core:jackson-databind (maven) versions >= 2.21.0, = 3.0.0, < 3.1.4.

Is there a fix for CVE-2026-54518?

Yes. CVE-2026-54518 is fixed in 2.21.4, 3.1.4. Upgrade to this version or later.

Is CVE-2026-54518 exploitable, and should I be worried?

Whether CVE-2026-54518 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk.

What actually determines whether CVE-2026-54518 is exploitable, and how bad it is?

Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.

CVE-2026-54518

Q: How severe is CVE-2026-54518?

CVE-2026-54518 has a CVSS score of 6.5 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.

Q: Which packages are affected by CVE-2026-54518?

com.fasterxml.jackson.core:jackson-databind (maven) versions >= 2.21.0, = 3.0.0, < 3.1.4.

Q: Is there a fix for CVE-2026-54518?

Yes. CVE-2026-54518 is fixed in 2.21.4, 3.1.4. Upgrade to this version or later.

Q: Is CVE-2026-54518 exploitable, and should I be worried?

Whether CVE-2026-54518 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk.

Q: What actually determines whether CVE-2026-54518 is exploitable, and how bad it is?

Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.

Q: How do I fix CVE-2026-54518?

Upgrade: com.fasterxml.jackson.core:jackson-databind to 2.21.4 or later, tools.jackson.core:jackson-databind to 3.1.4 or later.

Summary

jackson-databind has a @JsonView bypass for unwrapped creator parameters

Full technical description

UnwrappedPropertyHandler.processUnwrappedCreatorProperties() replays buffered JSON into creator parameters but never consults prop.visibleInView(activeView). The normal property-based creator path gates creator properties on the active view, but this unwrapped-creator replay path bypasses that check, so a constructor parameter annotated with both @JsonView(AdminView.class) and @JsonUnwrapped is populated from attacker JSON even when a more restrictive view is active.

Affected / Patched (verified via `git tag --contains`)

2.21 line: >= 2.21.0, < 2.21.4 -> fixed in 2.21.4 (backport 721fa07, #5973)
3.x line: >= 3.0.0, < 3.1.4 -> fixed in 3.1.4 (#5971, d633bc0)

Severity / CWE

Maintainer: minor. Reporter: HIGH. CWE-863 (Incorrect Authorization); related CWE-284.

Credits

Omkhar Arasaratnam (@omkhar) - finder.

Impact

View-restricted unwrapped creator parameters can be set from untrusted input where @JsonView is used as a write-side authorization boundary.

The application does not correctly enforce access controls, allowing a principal to access resources or operations beyond their granted permissions. Typical impact: unauthorized data access or execution of privileged operations.

CVE-2026-54518 has a CVSS score of 6.5 (Medium). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (2.21.4, 3.1.4); upgrading removes the vulnerable code path.

Affected versions

com.fasterxml.jackson.core:jackson-databind (>= 2.21.0, < 2.21.4) tools.jackson.core:jackson-databind (>= 3.0.0, < 3.1.4)

Security releases

com.fasterxml.jackson.core:jackson-databind → 2.21.4 (maven) tools.jackson.core:jackson-databind → 3.1.4 (maven)

Kodem intelligence

Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.

Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.

Already deployed Kodem?

See it in your environment New to Kodem? Get a demo →

Remediation advice

Upgrade the following packages to resolve this vulnerability:

com.fasterxml.jackson.core:jackson-databind to 2.21.4 or later; tools.jackson.core:jackson-databind to 3.1.4 or later

Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.

Frequently Asked Questions

What is CVE-2026-54518? CVE-2026-54518 is a medium-severity incorrect authorization vulnerability in com.fasterxml.jackson.core:jackson-databind (maven), affecting versions >= 2.21.0, < 2.21.4. It is fixed in 2.21.4, 3.1.4. The application does not correctly enforce access controls, allowing a principal to access resources or operations beyond their granted permissions.
How severe is CVE-2026-54518? CVE-2026-54518 has a CVSS score of 6.5 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
Which packages are affected by CVE-2026-54518?
- com.fasterxml.jackson.core:jackson-databind (maven) (versions >= 2.21.0, < 2.21.4)
- tools.jackson.core:jackson-databind (maven) (versions >= 3.0.0, < 3.1.4)
Is there a fix for CVE-2026-54518? Yes. CVE-2026-54518 is fixed in 2.21.4, 3.1.4. Upgrade to this version or later.
Is CVE-2026-54518 exploitable, and should I be worried? Whether CVE-2026-54518 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
What actually determines whether CVE-2026-54518 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
How do I fix CVE-2026-54518?
- Upgrade com.fasterxml.jackson.core:jackson-databind to 2.21.4 or later
- Upgrade tools.jackson.core:jackson-databind to 3.1.4 or later

Other vulnerabilities in com.fasterxml.jackson.core:jackson-databind

CVE-IDSeverityPackage summary

CVE-2026-54517Mediumcom.fasterxml.jackson.core:jackson-databind: jackson-databind has @JsonView bypass for setterless creator properties CVE-2026-54516Mediumcom.fasterxml.jackson.core:jackson-databind: jackson-databind's renamed @JsonIgnore'd setters can deserialize via private fields CVE-2026-54515Mediumcom.fasterxml.jackson.core:jackson-databind: jackson-databind has case-insensitive deserialization bypasses per-property @JsonIgnoreProperties CVE-2026-54514Mediumcom.fasterxml.jackson.core:jackson-databind: jackson-databind: InetSocketAddress deserialization triggers eager DNS resolution (SSRF)CVE-2026-54513Highcom.fasterxml.jackson.core:jackson-databind: jackson-databind has an array subtype allowlist bypass in BasicPolymorphicTypeValidator (allowIfSubTypeIsArray)