Nuclei: Local File Read via MySQL Client Sandbox Bypass

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

5.3 · CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:N/A:N

EPSS

• CVE-2026-76803: 0.40% estimated exploitation activity in the next 30 days; percentile 34.44 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

A vulnerability in Nuclei's JavaScript MySQL client library allows arbitrary local file reads that bypass the -allow-local-file-access (-lfa) sandbox restriction. Affected Component The issue is in the nuclei/mysql JavaScript library used by javascript: protocol templates. The MySQL client connection logic did not enforce the local file access sandbox when handling the allowAllFiles DSN parameter used by LOAD DATA LOCAL INFILE. Description Without -lfa, Nuclei confines local file access to the templates directory. However, a javascript: template could connect to a MySQL server with allowAllFiles=true in the connection DSN. With this option enabled, a malicious MySQL server can issue LOAD DATA LOCAL INFILE requests for arbitrary paths on the scanner host. The MySQL client reads the full file contents and sends them to the server, bypassing the same sandbox that blocks direct filesystem reads through other APIs. javascript: templates execute without the -code flag and unsigned…

Published by the source

22 Sep 2026, 20:37 UTC

Last modified by the source

1 Oct 2026, 20:45 UTC

Source last checked

26 Oct 2026, 15:29 UTC

1. Revision 3 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-xhmx-w2j4-rw3q

2. Revision 2 · amended · 24 Oct 2026

   Amended from osv record GO-2026-6577

3. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-xhmx-w2j4-rw3q

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# Patch Next advisory brief: CVE-2026-76803

Advisory: Nuclei: Local File Read via MySQL Client Sandbox Bypass
IDs: CVE-2026-76803, GHSA-xhmx-w2j4-rw3q
Record: https://patchnext.com/advisories/cve-2026-76803 (revision 3, source checked 26 Oct 2026, 15:29 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 5.3)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Partial vendor fix; fixed versions by package: github.com/projectdiscovery/nuclei/v3 3.10.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/projectdiscovery/nuclei: affected every version
- Go github.com/projectdiscovery/nuclei/v3: affected >= 3.0.0, < 3.10.0; fixed in 3.10.0
- Go github.com/projectdiscovery/nuclei/v2: affected every version

## Suggested inspection (read-only)
- Go github.com/projectdiscovery/nuclei: check the installed version with your package manager.
- Go github.com/projectdiscovery/nuclei/v3: check the installed version with your package manager.
- Go github.com/projectdiscovery/nuclei/v2: check the installed version with your package manager.

## Supported action
No complete vendor fix is recorded. Follow the primary source's mitigation guidance and check this record again before closing anything.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on github.com/projectdiscovery/nuclei, github.com/projectdiscovery/nuclei/v3, github.com/projectdiscovery/nuclei/v2.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GO-2026-6577 (OSV record GO-2026-6577 lists affected ranges: Go github.com/projectdiscovery/nuclei >=0; Go github.com/projectdiscovery/nuclei/v2 >=0; Go github.com/projectdiscovery/nuclei/v3 >=3.0.0 <3.10.0 (fixed))
- Verified: https://osv.dev/vulnerability/GHSA-xhmx-w2j4-rw3q (OSV record GHSA-xhmx-w2j4-rw3q lists affected ranges: Go github.com/projectdiscovery/nuclei/v3 >=3.0.0 <3.10.0 (fixed))
- Verified: https://github.com/advisories/GHSA-xhmx-w2j4-rw3q (GitHub-reviewed advisory GHSA-xhmx-w2j4-rw3q lists affected ranges: Go github.com/projectdiscovery/nuclei/v3 >=3.0.0 <3.10.0)

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