CVE-2022-39257
Matrix iOS SDK vulnerable to impersonation via forwarded Megolm sessions
Severity Score
Exploit Likelihood
Affected Versions
Public Exploits
0Exploited in Wild
-Decision
Descriptions
Matrix iOS SDK allows developers to build iOS apps compatible with Matrix. Prior to version 0.23.19, 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 matrix-ios-sdk implementing a too permissive key forwarding strategy. The default policy for accepting key forwards has been made more strict in the matrix-ios-sdk version 0.23.19. matrix-ios-sdk 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). This attack requires coordination between a malicious home server and an attacker, so those who trust their home servers do not need a workaround.
Matrix iOS SDK permite a los desarrolladores crear aplicaciones para iOS compatibles con Matrix. En versiones anteriores a 0.23.19, un atacante que colabore 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 que el matrix-ios-sdk implementa una estrategia de reenvío de claves demasiado permisiva. La política por defecto para aceptar reenvíos de claves se ha hecho más estricta en matrix-ios-sdk versión 0.23.19. matrix-ios-sdk ahora sólo aceptará claves reenviadas en respuesta a peticiones previamente emitidas y sólo desde dispositivos propios y verificados. El SDK ahora establece un flag "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). Este ataque requiere la coordinación entre un servidor doméstico malicioso y un atacante, por lo que aquellos que confían en sus servidores domésticos no necesitan una mitigación
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-ios-sdk/releases/tag/v0.23.19 | Release Notes | |
| https://github.com/matrix-org/matrix-ios-sdk/security/advisories/GHSA-qxr3-5jmq-xcf4 | Third Party Advisory |
| URL | Date | SRC |
|---|
| URL | Date | SRC |
|---|---|---|
| https://github.com/matrix-org/matrix-ios-sdk/commit/5ca86c328a5faaab429c240551cb9ca8f0f6262c | 2022-09-30 |
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" | < 0.23.19 Search vendor "Matrix" for product "Software Development Kit" and version " < 0.23.19" | iphone_os |
Affected
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