highVulnerability

CVE-2026-62673

## Summary The default `.htaccess` shipped with Grav (and the reference `webserver-configs/htaccess.txt`) contains security rules that block direct HTTP access to sensitive file types (`.yaml`, `.yml`, `.php`, `.json`, `.twig`, etc.) under `user/` and `system/vendor/` directories. However, these rules lack the `[NC]` (No Case) flag, making them case-sensitive. On case-insensitive filesystems (Windows/NTFS, macOS/HFS+, or Linux with Docker volumes mounted from Windows/macOS), an attacker can bypass these rules by requesting files with uppercase extensions (e.g., `.YAML`, `.PHP`, `.JSON`). ## Affected Versions - Grav 2.0.1 (latest stable as of June 2026) — confirmed - Grav 1.7.x — likely affected (same `.htaccess` rules) - All versions shipping the current `webserver-configs/htaccess.txt` ## Affected Component File: `.htaccess` (root of Grav installation) Reference: `webserver-configs/htaccess.txt` ## Affected Rules (lines 68, 70, 72) ```apache # Line 68 — system/vendor file types RewriteRule ^(system|vendor)/(.*)\.(txt|xml|md|html|htm|shtml|shtm|json|yaml|yml|php|php2|php3|php4|php5|phar|phtml|pl|py|cgi|twig|sh|bat)$ error [F] # Line 70 — user file types RewriteRule ^(user)/(.*)\.(txt|md|json|yaml|yml|php|php2|php3|php4|php5|phar|phtml|pl|py|cgi|twig|sh|bat)$ error [F] # Line 72 — .md files globally RewriteRule \.md$ error [F] ``` All three rules use `[F]` without `[NC]`, making the extension match case-sensitive. ## Steps to Reproduce 1. Install Grav on a system with a case-insensitive filesystem: - Windows (native WAMP/XAMPP) - macOS (default HFS+) - Docker on Windows/macOS with volume mounts (e.g., `./data:/var/www/html`) 2. Create or use any plugin that stores sensitive data in its YAML config (e.g., API keys): ``` user/plugins/my-plugin/my-plugin.yaml ``` 3. Request the file with a case-varied extension: ``` GET /user/plugins/my-plugin/my-plugin.YAML HTTP/1.1 ``` 4. **Expected**: HTTP 403 Forbidden 5. **Actual**: HTTP 20

Properties

ghsa_id
GHSA-vwg3-w8w3-pc79
severity
high
summary
Grav: .htaccess file extension rules bypass via case variation on case-insensitive filesystems
cve_id
CVE-2026-62673
is_ghsa_only
false
ghsa_published
2026-08-19T19:32:38Z
source_url
https://github.com/advisories/GHSA-vwg3-w8w3-pc79
ghsa_updated
2026-08-19T19:32:42Z

Related Entities (4)

VULNERABLE_TO (1)

[Software]composer/getgrav/grav

AFFECTS (1)

[Software]composer/getgrav/grav

HAS_WEAKNESS (1)

[Weakness]Improper Handling of Case Sensitivity

REPORTED_BY (1)

[Source]GitHub Advisory Database

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CVE-2026-62673 — Ninja Signal Threat Intelligence | Ninja Signal