Eclipse KeyPont MarshalJSON JwtClaims.MarshalJSON input validation

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.3$0-$5k2.34

Summaryinfo

A vulnerability categorized as problematic has been discovered in Eclipse KeyPont. This affects the function JwtClaims.MarshalJSON of the component MarshalJSON. Such manipulation leads to input validation. This vulnerability is documented as CVE-2026-89315. The attack can be executed remotely. There is not any exploit available.

Detailsinfo

A vulnerability was found in Eclipse KeyPont (affected version unknown). It has been rated as problematic. Affected by this issue is the function JwtClaims.MarshalJSON of the component MarshalJSON. The manipulation with an unknown input leads to a input validation vulnerability. Using CWE to declare the problem leads to CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. Impacted is availability. CVE summarizes:

`JwtClaims.MarshalJSON` built a Go struct at runtime with `reflect.StructOf`, synthesising a field named `"A" + claimName` for each untyped claim. `reflect.StructOf` **panics** when a field name is not a valid Go identifier, or when it duplicates another field. Both conditions are reachable from ordinary JWT claim names.

The advisory is shared for download at github.com. This vulnerability is handled as CVE-2026-89315 since 09/11/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 10/23/2026).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Vendor

Name

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.3

VulDB Base Score: 5.3
VulDB Temp Score: 5.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Input validation
CWE: CWE-20
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

09/11/2026 CVE reserved
10/23/2026 +42 days Advisory disclosed
10/23/2026 +0 days VulDB entry created
10/23/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-89315 (🔒)
GCVE (CVE): GCVE-0-2026-89315
GCVE (VulDB): GCVE-100-425636

Entryinfo

Created: 10/23/2026 11:17
Changes: 10/23/2026 11:17 (65)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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