How severe is GHSA-m48g-4wr2-j2h6?

GHSA-m48g-4wr2-j2h6 has a CVSS score of 6.2/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by GHSA-m48g-4wr2-j2h6?

GHSA-m48g-4wr2-j2h6 affects the following packages: @tinacms/cli (npm). Ecosystems affected: npm.

How do I fix GHSA-m48g-4wr2-j2h6?

Update @tinacms/cli to 2.1.8 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-m48g-4wr2-j2h6 is resolved across your whole dependency graph.

How do I detect GHSA-m48g-4wr2-j2h6 in my npm dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for @tinacms/cli. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

How do I mitigate GHSA-m48g-4wr2-j2h6 if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

How does O3 Security protect against GHSA-m48g-4wr2-j2h6?

O3 pinpoints whether GHSA-m48g-4wr2-j2h6 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is GHSA-m48g-4wr2-j2h6 actively exploited in the wild?

No public exploit code has been indexed for GHSA-m48g-4wr2-j2h6 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for GHSA-m48g-4wr2-j2h6?

GHSA-m48g-4wr2-j2h6 has an EPSS (Exploit Prediction Scoring System) score of 1.0%, placing it in the 59th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is GHSA-m48g-4wr2-j2h6?

GHSA-m48g-4wr2-j2h6 is classified as Information Exposure (CWE-200), CWE-552 (CWE-552). These weakness types describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

Is there exploit tooling available for GHSA-m48g-4wr2-j2h6?

A Nuclei detection template exists for GHSA-m48g-4wr2-j2h6, meaning automated scanners can fingerprint it. Public exploit tooling significantly increases real-world risk — prioritize patching and ensure detection coverage. Exploit tooling should only ever be used in isolated, authorized testing environments.

When was GHSA-m48g-4wr2-j2h6 published, and has it been updated?

GHSA-m48g-4wr2-j2h6 was published on March 12, 2026 and was last updated on March 14, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

📦 npm

GHSA-m48g-4wr2-j2h6

MEDIUM

TinaCMS CLI has Arbitrary File Read via Disabled Vite Filesystem Restriction

Also known asCVE-2026-29066

Published

Mar 12, 2026

Updated

Mar 14, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

EPSS Exploitation Probability

via FIRST.org ↗

1.0%probability of exploitation in next 30 days

Lower Risk59th percentile-5.45%

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Blast Radius

1 pkg affected

Weekly download volume for affected packages — a proxy for how broadly this vulnerability is deployed.

@tinacms/clinpm

38Kdownloads / week

Description

Summary

The TinaCMS CLI dev server configures Vite with server.fs.strict: false, which disables Vite's built-in filesystem access restriction. This allows any unauthenticated attacker who can reach the dev server to read arbitrary files on the host system

Details

When running tinacms dev, the CLI starts a Vite dev server configured in: packages/@tinacms/cli/src/next/vite/index.ts

server: {
  host: configManager.config?.build?.host ?? false,
  ...
  fs: {
    strict: false, // Disables Vite's filesystem access restriction
  },
},

TinaCMS middleware only intercepts specific route prefixes (/media/*, /graphql, /altair, /searchIndex). Any request to a path outside these routes falls through to Vite's default static file handler, which will serve the file directly from the absolute path on the filesystem. Additionally, the server enables permissive CORS (cors() with no origin restriction), which may further facilitate browser-based exploitation such as DNS rebinding attacks.

PoC

Prerequisites: TinaCMS CLI dev server running (default port 4001).

Read system files directly:

curl http://localhost:4001/etc/passwd

curl http://localhost:4001/etc/hostname

<img width="631" height="41" alt="image" src="https://github.com/user-attachments/assets/bd103dc3-d4c3-4774-8007-b55de3fc2a9e" /> Vite resolves and serves the absolute path directly from the filesystem.

Impact

Any developer running tinacms dev in an environment where the dev server port is reachable by an attacker. This includes:

Cloud IDEs (GitHub Codespaces, Gitpod) where ports are automatically forwarded and publicly accessible
Docker or VM setups with port forwarding configured
Misconfigured environments binding to 0.0.0.0 via the build.host config option
Systems targeted via DNS rebinding attacks, leveraging the unrestricted CORS policy
Local environments with malicious dependencies running on the same machine

An attacker who can reach port 4001 can:

Read any file readable by the server process (/etc/passwd, /etc/shadow, SSH private keys)
Exfiltrate environment variables and secrets via /proc/self/environ
Access cloud credentials and API keys from configuration files

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
📦npm	`@tinacms/cli`	all versions	2.1.8

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for @tinacms/cli. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update @tinacms/cli to 2.1.8 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-m48g-4wr2-j2h6 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-m48g-4wr2-j2h6 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to GHSA-m48g-4wr2-j2h6. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

## Summary The TinaCMS CLI dev server configures Vite with `server.fs.strict: false`, which disables Vite's built-in filesystem access restriction. This allows any unauthenticated attacker who can reach the dev server to read arbitrary files on the host system ## Details When running `tinacms dev`, the CLI starts a Vite dev server configured in: `packages/@tinacms/cli/src/next/vite/index.ts` ``` server: { host: configManager.config?.build?.host ?? false, ... fs: { strict: false, // Disables Vite's filesystem access restriction }, }, ``` TinaCMS middleware only intercepts specific

O3 Security · Impact-Aware SCA

Is GHSA-m48g-4wr2-j2h6 in your dependencies?

O3 detects GHSA-m48g-4wr2-j2h6 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

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