Threats affecting pkg:github/dmonad/lib0

CVE-2026-102521 is a high-severity out-of-bounds read vulnerability in the decoder function `readFromDataView` of the dmonad lib0 library versions up to 0.2.118. The flaw allows the decoder to read beyond its intended buffer boundaries, potentially exposing adjacent process memory such as credentials or logs. This vulnerability does not affect integrity or availability but can lead to information disclosure. It is similar to a previously known issue (GHSA-r5c8-rf4w-qrq8) but distinct in its specifics. No known exploits are reported in the wild, and no official patch or remediation details are provided in the input data.

A missing bounds check in the binary decoder in lib0, versions 0.2.1-0.2.117 and earlier and 1.0.0-rc.32 and earlier, lets any unauthenticated remote peer read adjacent process memory and receive it back. `readUint8Array` never compares the wire-supplied length against the decoder's own view, so one over-long length prefix returns whatever the host process allocated next: other tenants' document content, personal data, and live bearer session tokens**, recovered in full and at will. An attacker who can supply bytes to a lib0 decoder which means any peer that can open a socket, including before authentication reads adjacent process memory and, where the consumer echoes, stores or re-serves the decoded value, receives it back. This is patched in version 0.2.118 and 1.0.0-rc.33.