CVE-2024-47080
matrix-js-sdk keys sent via `sendSharedHistoryKeys` vulnerable to interception by malicious homeserver
No known exploitation. EPSS puts it in the 50th percentile. A vendor fix is available.
What to do
The vendor has published a fix. Version details are below where the sources state them.
What it is
From the CVE record
matrix-js-sdk is the Matrix Client-Server SDK for JavaScript and TypeScript. In matrix-js-sdk versions versions 9.11.0 through 34.7.0, the method `MatrixClient.sendSharedHistoryKeys` is vulnerable to interception by malicious homeservers. The method was introduced by MSC3061) and is commonly used to share historical message keys with newly invited users, granting them access to past messages in the room. However, it unconditionally sends these "shared" keys to all of the invited user's devices, regardless of whether the user's cryptographic identity is verified or whether the user's devices are signed by that identity. This allows the attacker to potentially inject its own devices to receive sensitive historical keys without proper security checks. Note that this only affects clients running the SDK with the legacy crypto stack. Clients using the new Rust cryptography stack (i.e. those that call `MatrixClient.initRustCrypto()` instead of `MatrixClient.initCrypto()`) are unaffected by this vulnerability, because `MatrixClient.sendSharedHistoryKeys()` raises an exception in such environments. The vulnerability was fixed in matrix-js-sdk 34.8.0 by removing the vulnerable functionality. As a workaround, remove use of affected functionality from clients.
In plain language
No plain-language summary for this CVE yet.
Exploitation
Where each signal puts this CVE on the scale from published to confirmed exploited.
- CISA KEV
Not in the catalog. CISA has not confirmed exploitation.
- Public exploits
No public exploit or proof of concept found in the sources we track.
- EPSS
0.7% chance of exploitation activity in the next 30 days, which ranks it in the 50th percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
5 events over 1 day, from the signal feeds we watch.
- Patch availablerecord updated
- Publishedweakness classified, att&ck mapped
Affected products
Technical detail
CVSS 3.1 vector
Open in the CVSS calculatorAV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Scored 5.3 by bdu.
How it is reached
- Access Vector NetworkExploitable remotely over the network
- Access Complexity LowNo special conditions required
Impact if exploited
- Confidentiality L
- Integrity NoneNo integrity impact
- Availability NoneNo availability impact
Weaknesses
ATT&CK techniques
Mapped from the weaknesses above (CWE to ATT&CK), not observed in attacks.
Sources
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