CVE-2026-44459 affects the hono framework's JWT utility where the NumericDate claims exp, nbf, and iat are improperly validated. Tokens containing malformed claim values can bypass time-based verification checks, potentially allowing acceptance of expired or not-yet-valid tokens. This issue only manifests if the verify() function processes such tokens, which typically requires attacker control over token issuance or signing keys. The vulnerability is resolved in hono version 4.12.18.

The vulnerability allows tokens with invalid time claims to bypass expiration and validity checks, potentially leading to acceptance of tokens outside their intended validity window. However, exploitation requires high privileges such as control over token issuance or signing keys, limiting the risk to scenarios where the attacker already has significant access. The CVSS score is 3.8 (low), reflecting limited impact and exploitability.

Upgrade hono to version 4.12.18 or later, where this vulnerability is fixed. Since the issue is resolved in this version, applying the official update is the recommended remediation. No additional mitigation is indicated.