# CVE-2026-103475: yii2-starter-kit through 4.2.0 Debug and Gii Module Exposure

> Default configuration exposes debug and Gii modules, allowing attackers to read sensitive data or execute code via file generation.

- **Severity:** Critical 9.3 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/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:** No
- **Published:** 30 Sep 2026
- **Updated:** 30 Sep 2026
- **Also known as:** GHSA-92vv-q57x-j4vj

## What is CVE-2026-103475?

CVE-2026-103475 is a critical vulnerability in yii2-starter-kit, published on 30 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

yii2-starter-kit through 4.2.0 exposes the Yii debug and Gii modules to all IP addresses by setting allowedIPs to ['*'] in its default development configuration. Unauthenticated remote attackers can access the debug endpoint to read sensitive data including session cookies and database queries, or access the Gii endpoint to generate and write PHP files into the application directory.

Weakness: CWE-489 (Active Debug Code)

## Which versions are affected by CVE-2026-103475?


## How do I fix CVE-2026-103475?

No fix has been published for CVE-2026-103475 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-103475 being exploited?

There is no known exploitation of CVE-2026-103475 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-103475 and fix it if it is affected.

What it is: CVE-2026-103475 is a critical vulnerability in yii2-starter-kit, published on 30 Sep 2026. 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-2026-103475 in the wild and no public exploit code.

Affected product: yii2-starter-kit. No package-level version data is available, so check the vendor advisory linked from the reference page.

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-2026-103475/ (Markdown: https://insights.sbomify.com/CVE-2026-103475/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-103475
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-103475
- OSV: https://osv.dev/vulnerability/CVE-2026-103475

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-103475/
Summaries are generated and may contain mistakes; the official description above is the record.