CVE-2026-15158 Blocksy Companion <= 2.1.46 - Unauthenticated Arbitrary File Upload via 'blc-review-images[]' Parameter
Unauthenticated attackers can upload executable files via double-extension bypass in Blocksy Companion Pro, leading to remote code execution.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-15158?
CVE-2026-15158 is a critical vulnerability in creativethemeshq Blocksy Companion, published on 9 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
The Blocksy Companion plugin for WordPress is vulnerable to Arbitrary File Upload in all versions up to, and including, 2.1.46 via the save_attachments function. This is due to the Custom Fonts extension registering a wp_check_filetype_and_ext filter that approves any filename containing .woff2 or .ttf as a substring via strpos() rather than validating that those strings appear as the final extension via PATHINFO_EXTENSION — allowing double-extension filenames such as shell.woff2.php to pass MIME validation and be handled as permitted font files. This makes it possible for unauthenticated attackers to upload files that may be executable, which makes remote code execution possible. This vulnerability is only exploitable when the premium version of the plugin (blocksy-companion-pro) is installed with both the WooCommerce Extra (Advanced Reviews) and Custom Fonts extensions active; the free blocksy-companion plugin does not contain the vulnerable code paths.
Weakness: CWE-434
Which versions are affected by CVE-2026-15158?
How do I fix CVE-2026-15158?
No fix has been published for CVE-2026-15158 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-15158 being exploited?
There is no known exploitation of CVE-2026-15158 in the wild and no public exploit code.
Sources
Also known as GHSA-hhjp-58g7-3jr8.