Out-of-bounds Read in Ruby JSON Parser

Answer in brief

CVE-2025-27788 records a High severity (CVSS 7.5) vulnerability in Out-of-bounds Read in Ruby JSON Parser. The current sources do not mark it as known exploited. The current feed maps json (rubygems). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

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

Published Mar 12, 2025Updated Sep 10, 2026Source checked Sep 10, 2026First seen by HOL Aug 7, 2026Material review Sep 10, 2026

Upstream Advisory

Key facts

Risk: High · CVSS 7.5
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Available

Why this deserves its current priority

CVSS is 7.5. 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 json (rubygems). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
jsonrubygems	>=2.10.0 <2.10.2	2.10.2

Recommended response

Check inventory. Check lockfiles and deployed manifests for json.
Review the reported fix. Update json to 2.10.2 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Mar 12, 2025
Evidence: source:osv:source_dates:source-dates:record
Source modified
Sep 10, 2026
Evidence: source:osv:source_dates:source-dates:record
First seen by HOL
Aug 7, 2026

Sources and claim methodology

Upstream source description

### Impact A specially crafted document could cause an out of bound read, most likely resulting in a crash. Versions 2.10.0 and 2.10.1 are impacted. Older versions are not. ### Patches Version 2.10.2 fixes the problem. ### Workarounds None.

Quoted source text, attributed separately from HOL analysis.