CVE-2026-89315

MEDIUMCVSS 6.9/10EPSS 0.25%

Last modified

CVE-2026-89315 is a medium-severity vulnerability rated 6.9/10 on the CVSS scale. `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. EPSS estimates a 0.25% chance of exploitation in the next 30 days.

Description

`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.

Metrics

Weakness Enumeration

Affected Software

Source: CNA advisory (CVE.org). NVD analysis pending.

VendorProductVersions
Eclipse FoundationEclipse KeyPont - GOSE>= 0.7.3, <= 0.13.0-rc1
Eclipse FoundationEclipse KeyPont - GOSE< 1.0.0-rc4

References

Timeline

Published
Last Modified
Status
Deferred

Frequently Asked Questions

What is CVE-2026-89315?
`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.
How severe is CVE-2026-89315?
CVE-2026-89315 has a CVSS score of 6.9/10 (MEDIUM severity). The EPSS model estimates a 0.25% probability of exploitation in the next 30 days.
How do I fix CVE-2026-89315?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

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Source: NVD / NIST