# CVE-2025-27111: Escape Sequence Injection vulnerability in Rack lead to Possible Log Injection

> Attackers can inject escape sequences into logs via the X-Sendfile-Type header in Rack, potentially corrupting log files.

- **Severity:** Medium 6.9 (`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`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 4 Mar 2025
- **Updated:** 3 Nov 2025
- **Also known as:** DEBIAN-CVE-2025-27111, GHSA-8cgq-6mh2-7j6v, MINI-jfh5-32v2-f832, MINI-rm59-v5p9-c6cf, SUSE-SU-2025:1492-1, UBUNTU-CVE-2025-27111, openSUSE-SU-2025:14859-1

## What is CVE-2025-27111?

CVE-2025-27111 is a medium-severity vulnerability in rack, published on 4 Mar 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Rack is a modular Ruby web server interface. The Rack::Sendfile middleware logs unsanitised header values from the X-Sendfile-Type header. An attacker can exploit this by injecting escape sequences (such as newline characters) into the header, resulting in log injection. This vulnerability is fixed in 2.2.12, 3.0.13, and 3.1.11.

Weakness: CWE-93 (Improper Neutralization of CRLF Sequences), CWE-117 (Improper Output Neutralization for Logs)

## Which versions are affected by CVE-2025-27111?

6 open source packages ship an affected version, including rack. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `rack` | RubyGems | All versions | 2.2.12 |
| `rack` | RubyGems | All versions | 2.2.12 |
| `rack` | RubyGems | From 3.0 | 3.0.13 |
| `rack` | RubyGems | From 3.0 | 3.0.13 |
| `rack` | RubyGems | From 3.1 | 3.1.11 |
| `rack` | RubyGems | From 3.1 | 3.1.11 |
| `rubygem-rack-1_6` | openSUSE:Leap 15.6 | All versions | 1.6.8-150000.3.6.1 |
| `rubygem-rack-2.2` | openSUSE:Tumbleweed | All versions | 2.2.12-1.1 |

Products: Rack Rack.

## How do I fix CVE-2025-27111?

Upgrade rack to a fixed version for your release line: 2.2.12, 3.0.13 or 3.1.11.

## Is CVE-2025-27111 being exploited?

There is no known exploitation of CVE-2025-27111 in the wild and no public exploit code.

## Other vulnerabilities in rack

- [CVE-2026-34785](https://insights.sbomify.com/CVE-2026-34785/): Rack: Local file inclusion in `Rack::Static` via URL Prefix Matching (high 7.5)
- [CVE-2026-34827](https://insights.sbomify.com/CVE-2026-34827/): Rack: Algorithmic-Complexity DoS in Rack::Multipart::Parser (high 7.5)
- [CVE-2026-34829](https://insights.sbomify.com/CVE-2026-34829/): Rack: Denial of Service via Unbounded Multipart File Upload Without Content-Length (high 7.5)
- [CVE-2026-22860](https://insights.sbomify.com/CVE-2026-22860/): Rack has a Directory Traversal via Rack:Directory (high 7.5)
- [CVE-2025-61919](https://insights.sbomify.com/CVE-2025-61919/): Rack is vulnerable to a memory-exhaustion DoS through unbounded URL-encoded body parsing (high 7.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-27111 and fix it if it is affected.

What it is: CVE-2025-27111 is a medium-severity vulnerability in rack, published on 4 Mar 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2025-27111 in the wild and no public exploit code.

Affected packages and fixed versions:
- rack (RubyGems): affected all versions; fixed in 2.2.12
- rack (RubyGems): affected all versions; fixed in 2.2.12
- rack (RubyGems): affected from 3.0; fixed in 3.0.13
- rack (RubyGems): affected from 3.0; fixed in 3.0.13
- rack (RubyGems): affected from 3.1; fixed in 3.1.11
- rack (RubyGems): affected from 3.1; fixed in 3.1.11

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2025-27111/ (Markdown: https://insights.sbomify.com/CVE-2025-27111/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-27111
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-27111
- OSV: https://osv.dev/vulnerability/CVE-2025-27111

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-27111/
Summaries are generated and may contain mistakes; the official description above is the record.