CVE-2026-42462

Fedify is a TypeScript library for building federated server apps powered by ActivityPub. Prior to versions 1.9.11, 1.10.10, 2.0.18, 2.1.14, and 2.2.3, an attacker can make use of JSON-LD features to restructure a JSON-LD document that would change how Fedify interprets it without changing its Linked Data Signature, allowing them to alter a third-party signed activity they have received. Versions 1.9.11, 1.10.10, 2.0.18, 2.1.14, and 2.2.3 fix the issue.

CVSS v3 7.0 HIGH

7.0^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 4.7

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact HIGH

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/fedify-dev/fedify/releases/tag/2.2.3
https://github.com/fedify-dev/fedify/security/advisories/GHSA-9rfg-v8g9-9367

Configurations

No configuration.

History

23 Jul 2026, 09:10

Type	Values Removed	Values Added
Summary		(es) Fedify es una biblioteca TypeScript para construir aplicaciones de servidor federadas impulsadas por ActivityPub. Antes de las versiones 1.9.11, 1.10.10, 2.0.18, 2.1.14 y 2.2.3, un atacante puede hacer uso de las características de JSON-LD para reestructurar un documento JSON-LD que cambiaría cómo Fedify lo interpreta sin cambiar su Firma de Datos Enlazados, permitiéndoles alterar una actividad firmada por terceros que hayan recibido. Las versiones 1.9.11, 1.10.10, 2.0.18, 2.1.14 y 2.2.3 solucionan el problema.

10 Jun 2026, 22:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-10 22:16

Updated : 2026-07-23 09:10

NVD link : CVE-2026-42462

Mitre link : CVE-2026-42462

CVE.ORG link : CVE-2026-42462

JSON object : View

Products Affected

No product.

CWE

CWE-180

Incorrect Behavior Order: Validate Before Canonicalize

CWE-347

Improper Verification of Cryptographic Signature

CWE-436

Interpretation Conflict

CWE-1289

Improper Validation of Unsafe Equivalence in Input

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