lib0 `readFromDataView` out-of-bounds read

Answer in brief

CVE-2026-102521 records a High severity (CVSS 8.6) vulnerability in lib0 `readFromDataView` out-of-bounds read. The current sources do not mark it as known exploited. The current feed maps dmonad/lib0 (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 29, 2026Updated Sep 29, 2026Source checked Sep 29, 2026First seen by HOL Sep 29, 2026Material review Sep 29, 2026

Upstream Advisory

Key facts

Risk: High · CVSS 8.6
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Available

Why this deserves its current priority

CVSS is 8.6. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps dmonad/lib0 (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
dmonad/lib0generic	<=0.2.118	= 0.2.118

Recommended response

Check inventory. Check lockfiles and deployed manifests for dmonad/lib0.
Review the reported fix. Update dmonad/lib0 to = 0.2.118 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Sep 29, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 29, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 29, 2026

Sources and claim methodology

Upstream source description

The decoder in `readFromDataView` in lib0 before 0.2.119 can be tricked into reading more than it should from a buffer. The vulnerability allows reading past the decoders' view, thus exposing adjacent process memory. This can be anything that is currently in the head, for example credentials or logs. This is similar to but different from GHSA-r5c8-rf4w-qrq8.

Quoted source text, attributed separately from HOL analysis.