CVE-2026-85097, Bricksforge for WordPress: an unauthenticated upload in the Pro Forms module writes attacker PHP into the uploads directory, exploited since 7 October; fixed in 4.0.1 and 3.1.8.10 (CVSS 9.8)
Bricksforge's Pro Forms upload flaw is exploited without login since 7 October; fixed in 4.0.1 and 3.1.8.10
Defender actions
- Find every WordPress site that your organisation, its web agencies or its hosting suppliers run with Bricksforge and update it to version 4.0.1 (3.1.8.10 on the 3.x line) now, treating any site that was reachable and unpatched since 2026-10-07 as one to search for dropped PHP files.
Analysis
Bricksforge's Pro Forms module checks a file's type when it is first uploaded but trusts the file metadata the client sends when the form is submitted, in particular the url field of the temporaryFileUploads parameter (Patchstack, 2026-10-08). An attacker obtains a nonce from the unauthenticated bricksforge_regenerate_nonce AJAX endpoint, uploads a GIF/PHP polyglot that passes the type check, then submits a form whose file path names that image and whose url ends in a PHP extension; the plugin writes the image's content to the PHP path and one request to it executes the code (Patchstack, 2026-10-08). Versions up to and including 3.1.8.9 are affected (Patchstack, 2026-10-08). The vendor's changelog lists the fix in 4.0.1 (Bricksforge, 2026-10-08), while Patchstack names 3.1.8.10 as the fixed build of the 3.x line, which the public changelog does not list (Dr. Web, 2026-10-09). Dr. Web credits Wordfence with a CVSS score of 9.8 and Patchstack with 10.0 (Dr. Web, 2026-10-09).
Patchstack's telemetry first recorded exploitation attempts on 2026-10-07 at 21:47 UTC, from 63 distinct source addresses, and it calls the activity automated without attributing it (Patchstack, 2026-10-08). Patchstack describes exploitation attempts and says an attacker with execution can deploy web shells, modify site content, read data and persist (Patchstack, 2026-10-08). It counts about 6,000 active installations (Dr. Web, 2026-10-09), Previdian tags the flaw "PoC available" (Previdian, 2026-10-08), and the flaw is not in CISA's KEV catalog (Dr. Web, 2026-10-09).
Cited evidence
This vulnerability is currently being targeted in the wild.
It affects every site with Pro Forms active, including sites whose forms use no upload fields, so updating is strongly recommended.
Patchstack has observed automated attacks from 63 different IP addresses since 7 October. (translated from German)
If the licence has lapsed, the fix may not arrive at all. (translated from German)
Previdian records an exploitation-related signal (poc available).
Sources4
AI-generated · no human review · this permalink is the shareable record for the finding · verify operationally critical claims against the linked primary source.