CVE-2026-41645
MediumCVSS 5.3Exploitation Probability (EPSS)
Low risk29th percentile - higher than 29% of all known CVEs
Summary
Nuclei is a vulnerability scanner built on a YAML-based DSL. From version 3.0.0 to before 3.8.0, a vulnerability in the expression evaluation engine allows a malicious target server to inject and execute supported DSL expressions. This occurs when HTTP response data containing helper/function syntax is reused by multi-step templates. If the -env-vars / -ev option is explicitly enabled, host environment variables may be exposed; the option is off by default.
Risk Assessment
The vulnerability could lead to execution of unauthorized DSL expressions and, if -env-vars is enabled, exposure of host environment variables, potentially resulting in leakage of sensitive information.
Recommendation
Update Nuclei to version 3.8.0 or later, which contains the patch. Avoid enabling the -env-vars / -ev option unless absolutely necessary.
Other vulnerabilities in Nuclei
See all- CVE-2026-76805Medium
In Nuclei from 3.0.0 until 3.10.0, the DAST/fuzz payload path in pkg/fuzz/parts.go can evaluate substituted runtime data more than once, creating a second evaluation pass that allows response content captured by an internal extractor to be reinterpreted as template syntax. When -env-vars is enabled, a malicious scan target can return marker-shaped content that discloses scanner-host environment variables such as credentials, API keys, or tokens.
- CVE-2026-76804Medium
In Nuclei from 3.0.0 until 3.10.0, the workflow template loading path does not enforce the -file capability gate when resolving file: protocol templates referenced by a workflow. An untrusted unsigned workflow can therefore load a file-protocol template and read local files from the scanner host even when the operator has not enabled file templates.
- CVE-2026-76803Medium
In Nuclei from 3.0.0 until 3.10.0, the nuclei/mysql JavaScript library does not enforce the local-file sandbox when a JavaScript template supplies the allowAllFiles MySQL DSN option. An untrusted javascript: template scanning an attacker-controlled MySQL-compatible endpoint can cause the server to issue LOAD DATA LOCAL INFILE requests for arbitrary paths, after which the scanner's MySQL client reads the files and returns their contents to the server even though -allow-local-file-access is disabled.
- CVE-2026-76802Medium
In Nuclei from 3.0.0 until 3.10.0, the DAST template loading branch does not apply the unsigned code-template signature check before accepting a template that contains both a fuzzing: block and an unsigned code: block. When an operator enables -dast, an untrusted multiprotocol template can place an unsigned code request into the execution queue and run arbitrary shell commands even without -code or a valid cryptographic signature.
- CVE-2026-92718High
Nuclei versions before 3.11.1 cache template signature verification based only on file modification time without content checksums. Attackers can replace verified templates with unsigned malicious content and restore the original modification time to bypass signature checks and execute arbitrary operating system commands.
- CVE-2026-41646Medium
In Nuclei versions 3.0.0 to before 3.8.0, a vulnerability in the JavaScript protocol runtime allows JavaScript templates to read local .js and .json files through the require() function, bypassing the default local file access restriction.
Original NVD description (English source)
Nuclei is a vulnerability scanner built on a simple YAML-based DSL. From version 3.0.0 to before version 3.8.0, a vulnerability in Nuclei's expression evaluation engine makes it possible for a malicious target server to inject and execute supported DSL expressions. This happens when HTTP response data containing helper/function syntax gets reused by multi-step templates. If the -env-vars / -ev option is explicitly enabled, this can expose host environment variables. That option is off by default, so standard configurations are not affected by the information disclosure risk. This issue has been patched in version 3.8.0.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS

