# CVE-2026-109425: Tink-go 2.8.0 Keyset Validation Bypass via NewHandleWithNoSecrets

Status: published. Published: 2026-10-12. Updated: 2026-11-08.

Tink-go (tink-crypto/tink-go) through 2.8.0 contains an input-validation vulnerability where keyset.NewHandleWithNoSecrets() and ReadWithNoSecrets() skip the structural Validate() step before constructing a keyset.Handle, allowing malformed public or no-secret keysets that violate Tink's keyset invariants to be accepted. Attackers can supply a malformed keyset, such as one with an enabled public key lacking a valid primary key or a DESTROYED key with no KeyData, causing inconsistent downstream validation where functions like jwt.JWKSetFromPublicKeysetHandle() process the invalid handle and produce a JWK set, potentially misleading applications that rely on successful handle construction as proof of keyset integrity.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- tink-crypto / tink-go (tink-crypto/tink-go): ≥ 2.0.0; ≤ 2.8.0 (affected, semver). Source: CNA: VulnCheck

## Severity and prioritization

- CVSS 4.0: 6.9 (medium); CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N; source: CNA: VulnCheck

- CVSS 3.1: 5.3 (medium); CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N; source: CNA: VulnCheck

- CISA KEV: No listing in collected sources

- EPSS: 0.19% as of 2026-11-08; percentile 8.99%

- SSVC: exploitation poc; automatable yes; technical impact partial; source ADP: CISA-ADP

- Weaknesses: CWE-1286

## Exploit evidence

- exploit: https://github.com/tink-crypto/tink-go/issues/68 (CNA: VulnCheck)

## References

- https://github.com/tink-crypto/tink-go/issues/68 (CNA: VulnCheck; technical-description, exploit, issue-tracking)

- https://www.vulncheck.com/advisories/tink-go-keyset-validation-bypass-via-newhandlewithnosecrets (CNA: VulnCheck; third-party-advisory)

## Provenance

- CNA: VulnCheck: https://www.cve.org/CVERecord?id=CVE-2026-109425; retrieved 2026-11-08; source updated 2026-11-08

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2026-109425; retrieved 2026-11-08; source updated Not reported

Revision: 54d04b4bb86d270b1f4799c0306fc9e2465196a50471004e5795a86315d73442

Canonical: https://y2.dev/cve/CVE-2026-109425

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