PYSEC-2026-252

    Dashboard / Vulnerabilities / PYSEC-2026-252

    PYSEC-2026-252

    Published: 29 Jun 2026Last Modified: 1 Jul 2026

    Summary: acryl-datahub missing JWT signature check

    Details: # Missing JWT signature check (`GHSL-2022-078`) The [`StatelessTokenService`](https://github.com/datahub-project/datahub/blob/aa146db611e3a4ca3aa17bb740783f789d4444d3/metadata-service/auth-impl/src/main/java/com/datahub/authentication/token/StatelessTokenService.java#L30) of the DataHub metadata service (GMS) does not verify the signature of JWT tokens. This allows an attacker to connect to DataHub instances as any user if Metadata Service authentication is enabled. This vulnerability occurs because the `StatelessTokenService` of the Metadata service uses the [`parse`](https://github.com/datahub-project/datahub/blob/aa146db611e3a4ca3aa17bb740783f789d4444d3/metadata-service/auth-impl/src/main/java/com/datahub/authentication/token/StatelessTokenService.java#L134) method of `io.jsonwebtoken.JwtParser`, which does not perform a verification of the cryptographic token signature. This means that JWTs are accepted regardless of the used algorithm. #### Impact This issue may lead to an authentication bypass. #### Resources * [CodeQL: Missing JWT signature check](https://codeql.github.com/codeql-query-help/java/java-missing-jwt-signature-check/)

    Affected packages

    Package

    Name: acryl-datahub

    Purl: pkg:pypi/acryl-datahub

    Affected ranges

    Type: ECOSYSTEM

    Events:

    Introduced- 0
    Fixed -0.8.45

    Affected versions

    0.0.2
    0.0.3
    0.0.4
    0.0.5

    Common Vulnerability Scoring System

    Attack Vector
    Network
    Adjacent
    Local
    Physical
    Privileges Required
    None
    Low
    High
    User Interaction
    None
    Required
    Scope
    Unchanged
    Changed
    Confidentiality
    None
    Low
    High
    Integrity
    None
    Low
    High
    Availability
    None
    Low
    High
    PYSEC-2026-252 | CVE-DB