onefetch through 2.28.1 Terminal Escape Sequence Injection (CVE-2026-100866) | HOL Guard CVE

Medium · CVSS 4.8CVE-2026-100866

onefetch through 2.28.1 Terminal Escape Sequence Injection

Answer in brief

CVE-2026-100866 records a Medium severity (CVSS 4.8) vulnerability in onefetch through 2.28.1 Terminal Escape Sequence Injection. The current sources do not mark it as known exploited. The current feed maps o2sh/onefetch (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 27, 2026Updated Sep 27, 2026Source checked Sep 27, 2026First seen by HOL Sep 27, 2026Material review Sep 27, 2026

Upstream Advisory

Key facts

Risk: Medium · CVSS 4.8
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Not reported

Why this deserves its current priority

CVSS is 4.8. 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 o2sh/onefetch (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
o2sh/onefetchgeneric	>=0 <=2.28.1	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for o2sh/onefetch.
Review the reported fix. Monitor this advisory for an available fix and review any installs of the affected package.

Evidence timeline and material changes

Published upstream
Sep 27, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 27, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 27, 2026

Sources and claim methodology

Upstream source description

onefetch through 2.28.1 writes repository information field values to the terminal without removing control characters, allowing terminal escape sequence injection. Attackers can embed ANSI/OSC escape sequences in project manifest version and name fields to manipulate terminal output, rewrite window titles, hide text, or trigger emulator-specific behavior when victims run onefetch.

Quoted source text, attributed separately from HOL analysis.