How severe is GHSA-h756-wh59-hhjv?

GHSA-h756-wh59-hhjv has a CVSS score of 8.8/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by GHSA-h756-wh59-hhjv?

GHSA-h756-wh59-hhjv affects the following packages: getgrav/grav (Packagist). Ecosystems affected: Packagist.

How do I fix GHSA-h756-wh59-hhjv?

Update getgrav/grav to 1.8.0-beta.27 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-h756-wh59-hhjv is resolved across your whole dependency graph.

How do I detect GHSA-h756-wh59-hhjv in my Packagist dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for getgrav/grav. 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-h756-wh59-hhjv 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-h756-wh59-hhjv?

O3 pinpoints whether GHSA-h756-wh59-hhjv 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-h756-wh59-hhjv actively exploited in the wild?

No public exploit code has been indexed for GHSA-h756-wh59-hhjv 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-h756-wh59-hhjv?

GHSA-h756-wh59-hhjv has an EPSS (Exploit Prediction Scoring System) score of 0.5%, placing it in the 37th 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-h756-wh59-hhjv?

GHSA-h756-wh59-hhjv is classified as Path Traversal (CWE-22). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

When was GHSA-h756-wh59-hhjv published, and has it been updated?

GHSA-h756-wh59-hhjv was published on December 2, 2025 and was last updated on December 2, 2025. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐘 Packagist

GHSA-h756-wh59-hhjv

HIGH

Grav vulnerable to Path traversal / arbitrary YAML write via user creation leading to Account Takeover / System Corruption

Also known asCVE-2025-66295

Published

Dec 2, 2025

Updated

Dec 2, 2025

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

EPSS Exploitation Probability

via FIRST.org ↗

0.5%probability of exploitation in next 30 days

Lower Risk37th percentile+0.36%

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

🐘getgrav/grav

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.

Description

Summary

When a user with privilege of user creation creates a new user through the Admin UI and supplies a username containing path traversal sequences (for example ..\Nijat or ../Nijat), Grav writes the account YAML file to an unintended path outside user/accounts/. The written YAML can contain account fields such as email, fullname, twofa_secret, and hashed_password. In my tests, I was able to cause the Admin UI to write the following content into arbitrary .yaml files (including files like email.yaml, system.yaml, or other site YAML files like admin.yaml) — demonstrating arbitrary YAML write / overwrite via the Admin UI.

Example observed content written by the Admin UI (test data): username: ..\Nijat state: enabled email: [email protected] fullname: 'Nijat Alizada' language: en content_editor: default twofa_enabled: false twofa_secret: RWVEIHC2AFVD6FCR6UHCO3DS4HWXKKDT avatar: { } hashed_password: $2y$10$wl9Ktv3vUmDKCt8o6u2oOuRZr1I04OE0YZf2sJ1QcAherbNnk1XVC access: site: login: true

Steps to Reproduce

Log in to the Grav Admin UI as an administrator.
Create a new user with the following values (example): a. Username: ..\POC-TOKEN-2025-09-29 b. Fullname: POC-TOKEN-2025-09-29 c. Email: [email protected] d. Password: (any password) Observe that a YAML file containing the POC-TOKEN is written outside user/accounts/ (for example in the parent directory of user/accounts)

Impact

Config corruption / service disruption: Overwriting system.yaml, email.yaml, or plugin config files with attacker-controlled YAML (even if limited to fields present in account YAML) could break functionality, disable services, or cause misconfiguration requiring recovery from backups.
Account takeover, any user with create user privilege can modify other user's email and password by just creating a new user with the name "..\accounts\USERNAME_OF_VICTIM"

Proof of Concept

https://github.com/user-attachments/assets/cf503d74-f765-4031-8e22-71f6b3630847

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐘Packagist	`getgrav/grav`	all versions	1.8.0-beta.27

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for getgrav/grav. 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 getgrav/grav to 1.8.0-beta.27 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-h756-wh59-hhjv 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-h756-wh59-hhjv 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-h756-wh59-hhjv. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

### Summary When a user with privilege of user creation creates a new user through the Admin UI and supplies a username containing path traversal sequences (for example ..\Nijat or ../Nijat), Grav writes the account YAML file to an unintended path outside user/accounts/. The written YAML can contain account fields such as email, fullname, twofa_secret, and hashed_password. In my tests, I was able to cause the Admin UI to write the following content into arbitrary .yaml files (including files like email.yaml, system.yaml, or other site YAML files like admin.yaml) — demonstrating arbitrary YAML

O3 Security · Impact-Aware SCA

Is GHSA-h756-wh59-hhjv in your dependencies?

O3 detects GHSA-h756-wh59-hhjv across Packagist 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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