CVE-2023-37896: Nuclei is a vulnerability scanner. (CVSS 7.5)

Nuclei is a vulnerability scanner.

Nuclei is a vulnerability scanner. Prior to version 2.9.9, a security issue in the Nuclei project affected users utilizing Nuclei as Go code (SDK) running custom templates. This issue did not affect CLI users. The problem was related to sanitization issues with payload loading in sandbox mode. There was a potential risk with payloads loading in sandbox mode. The issue occurred due to relative paths not being converted to absolute paths before doing the check for `sandbox` flag allowing arbitrary files to be read on the filesystem in certain cases when using Nuclei from `Go` SDK implementation. This issue has been fixed in version 2.9.9. The maintainers have also enabled sandbox by default for filesystem loading. This can be optionally disabled if required. The `-sandbox` option has been deprecated and is now divided into two new options: `-lfa` (allow local file access) which is enabled by default and `-lna` (restrict local network access) which can be enabled by users optionally. The `-lfa` allows file (payload) access anywhere on the system (disabling sandbox effectively), and `-lna` blocks connections to the local/private network.

Description from the National Vulnerability Database, published by GitHub

What it means for a small business

If your business uses nuclei, install the vendor's update. If you're not sure whether you use it, ask whoever manages your computers.

How likely is an attack? The Exploit Prediction Scoring System, run by FIRST (the global association of security response teams), puts the odds of this one being exploited in the next 30 days at 1.0%, higher than 64% of CVEs. That’s above average: worth scheduling this week. Scored October 29, 2026, updated daily.

Check your own setup

Website check: reads what your site runs from the outside (WordPress version, plugins it can see, old server software) and matches it against this database.
Server check: what your web server says about itself, and whether that version has known flaws.

Sources

Part of the Huttenlocher Technologies vulnerability database, refreshed twice a day from CISA and the NVD. The title, category and plain-language guidance are ours; check the linked record before acting on a detail. This is general guidance, not a review of your systems.

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