CVE-2026-42879
MEDIUMCVE-2026-42879 is a medium-severity (CVSS 6.3) Code Injection vulnerability in facturascripts/facturascripts. O3 Security confirms whether CVE-2026-42879 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
FacturaScripts: Authenticated Remote Code Execution (RCE) via GIF Image Upload in Product Images
Blast Radius
facturascripts/facturascriptsReal-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
FacturaScripts is an open source accounting and invoicing software. In 2025.81 and earlier, an authenticated unrestricted file upload vulnerability exists in FacturaScripts' product image upload functionality. An attacker with valid credentials can upload a PHP file disguised as a GIF image (using a GIF89a header), bypassing MIME type validation. The file is stored with its original extension, including executable extensions such as .php. The vulnerability exists the addImageAction() method of Core/Lib/ExtendedController/ProductImagesTrait.php.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | facturascripts/facturascripts | all versions | No fix |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for facturascripts/facturascripts. 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.
Remediation status
No patched version of facturascripts/facturascripts has shipped for CVE-2026-42879 yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.
Mitigate without a patch
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 CVE-2026-42879 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 CVE-2026-42879. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-42879 in your dependencies?
O3 detects CVE-2026-42879 across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.