CVE-2026-107720

Published: Ott 09, 2026 Last Modified: Ott 09, 2026

ExploitDB:

Other exploit source:

Google Dorks:

HIGH 7,4

Source: [email protected]

Attack Vector: network

Attack Complexity: high

Privileges Required: none

User Interaction: none

Scope: unchanged

Confidentiality: high

Integrity: high

Availability: none

Description

AI Translation Available

fast-jwt provides fast JSON Web Token (JWT) implementation. Prior to 6.3.1, fast-jwt createVerifier accepts an unsigned JWT when key is an empty string or null and algorithms is a non-empty allowlist. Falsy synchronous keys bypass prepareKeyOrSecret, allowedAlgorithms remains active, hasKey is false, and the empty signature avoids the verifySignature gate. An attacker can therefore submit a token containing arbitrary claims without possessing a signing key, resulting in authentication or authorization bypass. Claim validators still run, and non-empty keys, an empty key without algorithms, and the async key resolver path do not have this behavior. This issue is fixed in version 6.3.1.

EPSS (Exploit Prediction Scoring System)

Trend Analysis

EPSS (Exploit Prediction Scoring System)

Prevede la probabilità di sfruttamento basata su intelligence sulle minacce e sulle caratteristiche della vulnerabilità.

EPSS Score

0,0026

Percentile

0,2th

Updated

EPSS Score Trend (Last 3 Days)

Improper Input Validation

Stable

Abstraction: Class Structure: Simple

Common Consequences

Security Scopes Affected:

Availability Confidentiality Integrity

Potential Impacts:

Dos: Crash, Exit, Or Restart Dos: Resource Consumption (Cpu) Dos: Resource Consumption (Memory) Read Memory Read Files Or Directories Modify Memory Execute Unauthorized Code Or Commands