CVE-2022-39246
matrix-android-sdk2 vulnerable to impersonation via forwarded Megolm sessions
Severity Score
Exploit Likelihood
Affected Versions
Public Exploits
0Exploited in Wild
-Decision
Descriptions
matrix-android-sdk2 is the Matrix SDK for Android. Prior to version 1.5.1, an attacker cooperating with a malicious homeserver can construct messages appearing to have come from another person. Such messages will be marked with a grey shield on some platforms, but this may be missing in others. This attack is possible due to the key forwarding strategy implemented in the matrix-android-sdk2 that is too permissive. Starting with version 1.5.1, the default policy for accepting key forwards has been made more strict in the matrix-android-sdk2. The matrix-android-sdk2 will now only accept forwarded keys in response to previously issued requests and only from own, verified devices. The SDK now sets a `trusted` flag on the decrypted message upon decryption, based on whether the key used to decrypt the message was received from a trusted source. Clients need to ensure that messages decrypted with a key with `trusted = false` are decorated appropriately (for example, by showing a warning for such messages). As a workaroubnd, current users of the SDK can disable key forwarding in their forks using `CryptoService#enableKeyGossiping(enable: Boolean)`.
matrix-android-sdk2 es el SDK de Matrix para Android. En versiones anteriores a 1.5.1, un atacante que coopere con un servidor doméstico malicioso puede construir mensajes que parezcan proceder de otra persona. Dichos mensajes estarán marcados con un escudo gris en algunas plataformas, pero éste puede faltar en otras. Este ataque es posible debido a una estrategia de reenvío de claves implementada en el matrix-android-sdk2 que es demasiado permisiva. A partir de la versión 1.5.1, la política por defecto para aceptar reenvíos de claves es hecho más estricta en matrix-android-sdk2. El matrix-android-sdk2 ahora sólo aceptará claves reenviadas en respuesta a peticiones previamente emitidas y sólo de dispositivos propios y verificados. El SDK ahora establece un flag de "trusted" en el mensaje descifrado al descifrarlo, basándose en si la clave usada para descifrar el mensaje fue recibida de una fuente confiable. Los clientes deben asegurarse de que los mensajes descifrados con una clave con "trusted = false" sean decorados apropiadamente (por ejemplo, mostrando una advertencia para tales mensajes). Como mitigación, los usuarios actuales del SDK pueden deshabilitar el reenvío de claves en sus forks usando "CryptoService#enableKeyGossiping(enable: Boolean)"
CVSS Scores
SSVC
- Decision:-
Timeline
- 2022-09-02 CVE Reserved
- 2022-09-28 CVE Published
- 2024-04-20 EPSS Updated
- 2024-08-03 CVE Updated
- ---------- Exploited in Wild
- ---------- KEV Due Date
- ---------- First Exploit
CWE
- CWE-287: Improper Authentication
- CWE-322: Key Exchange without Entity Authentication
CAPEC
References (4)
| URL | Tag | Source |
|---|---|---|
| https://github.com/matrix-org/matrix-android-sdk2/releases/tag/v1.5.1 | Release Notes |
| URL | Date | SRC |
|---|
| URL | Date | SRC |
|---|
Affected Vendors, Products, and Versions
| Vendor | Product | Version | Other | Status | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Vendor | Product | Version | Other | Status | <-- --> | Vendor | Product | Version | Other | Status |
| Matrix Search vendor "Matrix" | Software Development Kit Search vendor "Matrix" for product "Software Development Kit" | < 1.5.1 Search vendor "Matrix" for product "Software Development Kit" and version " < 1.5.1" | android |
Affected
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