CVSS: 6.8EPSS: 0%CPEs: 2EXPL: 0CVE-2023-38691 – matrix-appservice-bridge doesn't verify the sub parameter of an openId token exhange, allowing unauthorized access to provisioning APIs
https://notcve.org/view.php?id=CVE-2023-38691
04 Aug 2023 — matrix-appservice-bridge provides an API for setting up bridges. Starting in version 4.0.0 and prior to versions 8.1.2 and 9.0.1, a malicious Matrix server can use a foreign user's MXID in an OpenID exchange, allowing a bad actor to impersonate users when using the provisioning API. The library does not check that the servername part of the `sub` parameter (containing the user's *claimed* MXID) is the the same as the servername we are talking to. A malicious actor could spin up a server on any given domain,... • https://github.com/matrix-org/matrix-appservice-bridge/commit/4c6723a5e7beda65cdf1ae5dbb882e8beaac8552 • CWE-287: Improper Authentication •
CVSS: 6.5EPSS: 0%CPEs: 1EXPL: 0CVE-2021-32659 – Automatic room upgrade handling can be used maliciously to bridge a room non-consentually
https://notcve.org/view.php?id=CVE-2021-32659
16 Jun 2021 — Matrix-appservice-bridge is the bridging service for the Matrix communication program's application services. In versions 2.6.0 and earlier, if a bridge has room upgrade handling turned on in the configuration (the `roomUpgradeOpts` key when instantiating a new `Bridge` instance.), any `m.room.tombstone` event it encounters will be used to unbridge the current room and bridge into the target room. However, the target room `m.room.create` event is not checked to verify if the `predecessor` field contains the... • https://github.com/matrix-org/matrix-appservice-bridge/commit/b69e745584a34fcfd858df33e4631e420da07b9f • CWE-306: Missing Authentication for Critical Function •