# Escape Sequence Injection vulnerability in Rack lead to Possible Log Injection

Advisory record · `GHSA-8cgq-6mh2-7j6v`

- **Identifiers:** `GHSA-8cgq-6mh2-7j6v` · `CVE-2025-27111`
- **State:** Confirmed
- **Severity:** CVSS 6.9 Medium
- **Critical:** No
- **Weakness (CWE):** [CWE-93](https://cwe.mitre.org/data/definitions/93.html) · [CWE-117](https://cwe.mitre.org/data/definitions/117.html)
- **Tags:** [Other injection](https://agentprime.io/advisories/tag/injection.md)
- **Published:** 4 Mar 2025
- **Updated:** 10 Sept 2026
- **Reviewed by a person:** No

Published by the GitHub Advisory Database at 4 Mar 2025, 15:27 UTC. agentprime has not analysed this yet, so whether it affects any app is not known.

## Affected packages

- `rack` (RubyGems): affected `<2.2.12 || >=3.0, <3.0.13 || >=3.1, <3.1.11`; fixed in `2.2.12`, `3.0.13`, `3.1.11`

## Not analysed yet

We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.

## Severity and exploitation

- 6.9 Medium, CVSS 4.0: `CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N`, from CNA (GitHub_M)

- **CISA KEV:** Not listed.
- **EPSS:** 0.0075, the 55th percentile, on 6 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

## Timeline

- 31 Oct 2026, 15:16 UTC: First seen by agentprime
- 31 Oct 2026, 15:16 UTC: [Confirmed by OSV](https://osv.dev/vulnerability/GHSA-8cgq-6mh2-7j6v)

## Sources

- [GitHub Advisory Database: GHSA-8cgq-6mh2-7j6v](https://github.com/advisories/GHSA-8cgq-6mh2-7j6v)
- [OSV: GHSA-8cgq-6mh2-7j6v](https://osv.dev/vulnerability/GHSA-8cgq-6mh2-7j6v)
- <https://github.com/rack/rack/security/advisories/GHSA-8cgq-6mh2-7j6v>
- <https://nvd.nist.gov/vuln/detail/CVE-2025-27111>
- <https://github.com/rack/rack/commit/803aa221e8302719715e224f4476e438f2531a53>
- <https://github.com/rack/rack/commit/aeac570bb8080ca7b53b7f2e2f67498be7ebd30b>
- <https://github.com/rack/rack/commit/b13bc6bfc7506aca3478dc5ac1c2ec6fc53f82a3>
- <https://github.com/rack/rack>
- <https://github.com/rubysec/ruby-advisory-db/blob/master/gems/rack/CVE-2025-27111.yml>
- <https://lists.debian.org/debian-lts-announce/2025/03/msg00016.html>

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.

## Check whether this affects you

A Match means an installed version is in the affected range above. Most don’t affect the app; agentprime hasn’t analysed this one yet.

- With the agentprime MCP server (<https://api.agentprime.io/mcp>), ask your agent to check the project: `check_lockfile` sends a lockfile, `check_packages` a list of installed packages, and both return the Matches and the upgrades that clear them. `get_advisory` returns this record. Setup: <https://agentprime.io/mcp.md>
- In a browser: <https://agentprime.io/check/> reads your lockfile in the browser, never uploading it.
- Whether it touches your code, with file and line: the Claude Code plugin, <https://agentprime.io/plugin.md>
- As JSON: <https://api.agentprime.io/v1/advisories/GHSA-8cgq-6mh2-7j6v>, or `POST https://api.agentprime.io/v1/match` with your packages (<https://agentprime.io/api.md>)

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The web page: <https://agentprime.io/advisories/GHSA-8cgq-6mh2-7j6v/>. Everything for agents: <https://agentprime.io/llms.txt>.