CWE-94
Allowed-with-ReviewImproper Control of Generation of Code ('Code Injection')
Abstraction: Base · Status: Draft
The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment.
8317 vulnerabilities reference this CWE, most recent first.
GHSA-33C7-2MPW-HG34
Vulnerability from github – Published: 2020-07-29 18:07 – Updated: 2024-11-18 22:32This affects all versions of package uvicorn. The request logger provided by the package is vulnerable to ASNI escape sequence injection. Whenever any HTTP request is received, the default behaviour of uvicorn is to log its details to either the console or a log file. When attackers request crafted URLs with percent-encoded escape sequences, the logging component will log the URL after it's been processed with urllib.parse.unquote, therefore converting any percent-encoded characters into their single-character equivalent, which can have special meaning in terminal emulators. By requesting URLs with crafted paths, attackers can: * Pollute uvicorn's access logs, therefore jeopardising the integrity of such files. * Use ANSI sequence codes to attempt to interact with the terminal emulator that's displaying the logs (either in real time or from a file).
{
"affected": [
{
"package": {
"ecosystem": "PyPI",
"name": "uvicorn"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "0.11.7"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2020-7694"
],
"database_specific": {
"cwe_ids": [
"CWE-116",
"CWE-94"
],
"github_reviewed": true,
"github_reviewed_at": "2020-07-29T17:37:27Z",
"nvd_published_at": "2020-07-27T12:15:00Z",
"severity": "HIGH"
},
"details": "This affects all versions of package uvicorn. The request logger provided by the package is vulnerable to ASNI escape sequence injection. Whenever any HTTP request is received, the default behaviour of uvicorn is to log its details to either the console or a log file. When attackers request crafted URLs with percent-encoded escape sequences, the logging component will log the URL after it\u0027s been processed with urllib.parse.unquote, therefore converting any percent-encoded characters into their single-character equivalent, which can have special meaning in terminal emulators. By requesting URLs with crafted paths, attackers can: * Pollute uvicorn\u0027s access logs, therefore jeopardising the integrity of such files. * Use ANSI sequence codes to attempt to interact with the terminal emulator that\u0027s displaying the logs (either in real time or from a file).",
"id": "GHSA-33c7-2mpw-hg34",
"modified": "2024-11-18T22:32:53Z",
"published": "2020-07-29T18:07:16Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2020-7694"
},
{
"type": "WEB",
"url": "https://github.com/encode/uvicorn/issues/723"
},
{
"type": "WEB",
"url": "https://github.com/encode/uvicorn/commit/895807f94ea9a8e588605c12076b7d7517cda503"
},
{
"type": "PACKAGE",
"url": "https://github.com/encode/uvicorn"
},
{
"type": "WEB",
"url": "https://github.com/pypa/advisory-database/tree/main/vulns/uvicorn/PYSEC-2020-150.yaml"
},
{
"type": "WEB",
"url": "https://snyk.io/vuln/SNYK-PYTHON-UVICORN-575560"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N",
"type": "CVSS_V4"
}
],
"summary": "Log injection in uvicorn"
}
GHSA-33GQ-CGFX-F6M6
Vulnerability from github – Published: 2022-05-01 18:39 – Updated: 2022-05-01 18:39Direct static code injection vulnerability in acp/savenews.php in Sciurus Hosting Panel, possibly 2.0.3, allows remote attackers to inject arbitrary PHP code via the filecontents parameter, which can be executed by accessing includes/news.php.
{
"affected": [],
"aliases": [
"CVE-2007-6082"
],
"database_specific": {
"cwe_ids": [
"CWE-94"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2007-11-22T00:46:00Z",
"severity": "HIGH"
},
"details": "Direct static code injection vulnerability in acp/savenews.php in Sciurus Hosting Panel, possibly 2.0.3, allows remote attackers to inject arbitrary PHP code via the filecontents parameter, which can be executed by accessing includes/news.php.",
"id": "GHSA-33gq-cgfx-f6m6",
"modified": "2022-05-01T18:39:31Z",
"published": "2022-05-01T18:39:31Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2007-6082"
},
{
"type": "WEB",
"url": "https://exchange.xforce.ibmcloud.com/vulnerabilities/38543"
},
{
"type": "WEB",
"url": "https://www.exploit-db.com/exploits/4635"
},
{
"type": "WEB",
"url": "http://securityreason.com/securityalert/3388"
},
{
"type": "WEB",
"url": "http://www.r57.li/exploit.txt"
},
{
"type": "WEB",
"url": "http://www.securityfocus.com/archive/1/483867/100/0/threaded"
},
{
"type": "WEB",
"url": "http://www.securityfocus.com/bid/26481"
}
],
"schema_version": "1.4.0",
"severity": []
}
GHSA-33GX-2JCQ-HQ54
Vulnerability from github – Published: 2022-05-17 05:45 – Updated: 2022-05-17 05:45phpMyFAQ 2.6.11 and 2.6.12, as distributed between December 4th and December 15th 2010, contains an externally introduced modification (Trojan Horse) in the getTopTen method in inc/Faq.php, which allows remote attackers to execute arbitrary PHP code.
{
"affected": [],
"aliases": [
"CVE-2010-4558"
],
"database_specific": {
"cwe_ids": [
"CWE-94"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2010-12-17T19:00:00Z",
"severity": "HIGH"
},
"details": "phpMyFAQ 2.6.11 and 2.6.12, as distributed between December 4th and December 15th 2010, contains an externally introduced modification (Trojan Horse) in the getTopTen method in inc/Faq.php, which allows remote attackers to execute arbitrary PHP code.",
"id": "GHSA-33gx-2jcq-hq54",
"modified": "2022-05-17T05:45:23Z",
"published": "2022-05-17T05:45:23Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2010-4558"
},
{
"type": "WEB",
"url": "http://secunia.com/advisories/42622"
},
{
"type": "WEB",
"url": "http://www.phpmyfaq.de/advisory_2010-12-15.php"
},
{
"type": "WEB",
"url": "http://www.securityfocus.com/bid/45442"
},
{
"type": "WEB",
"url": "http://www.vupen.com/english/advisories/2010/3254"
}
],
"schema_version": "1.4.0",
"severity": []
}
GHSA-33QF-Q99X-WPM8
Vulnerability from github – Published: 2026-04-16 21:28 – Updated: 2026-04-27 16:15Impact
Up to 1.0.0 of home-assitant-cli (or hass-cli for short) an unrestricted environment was used to handle Jninja2 templates instead of a sandboxed one. The user-supplied input within Jinja2 templates was rendered locally with no restrictions. This gave users access to Python's internals and extended the scope of templating beyond the intended usage.
E. g., it was possible to render a template with hass-cli template bad-template.j2 --local that contained entries like
{%- set b = environ.__globals__['__builtins__'] -%}
{%- set os = b['__import__']('os') -%}
{%- set bio = b['__import__']('builtins') -%}
...
or other malicious Jinja2 expressions. This can lead to arbitrary code execution on the local machine.
In a two step process an adversary could trick/convince an user to download third-party templates which contain harmful code (e. g., perform data manipulation or establish a remote shell) then to render those templates unchecked/reviewed/verified with --local.
The issue only affect the local machine and not a remote Home Assistant instance. It also requires user interventions.
Patches
1.0.0 uses ImmutableSandboxedEnvironment and restricts the usage of environment variables.
Workarounds
Evaluate the Jninja2 templates manually or tool-based before rendering with hass-cli.
{
"affected": [
{
"package": {
"ecosystem": "PyPI",
"name": "homeassistant-cli"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "1.0.0"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-40602"
],
"database_specific": {
"cwe_ids": [
"CWE-1336",
"CWE-94"
],
"github_reviewed": true,
"github_reviewed_at": "2026-04-16T21:28:39Z",
"nvd_published_at": "2026-04-21T18:16:51Z",
"severity": "MODERATE"
},
"details": "### Impact\n\nUp to 1.0.0 of `home-assitant-cli` (or `hass-cli` for short) an unrestricted environment was used to handle Jninja2 templates instead of a sandboxed one. The user-supplied input within Jinja2 templates was rendered locally with no restrictions. This gave users access to Python\u0027s internals and extended the scope of templating beyond the intended usage.\n\nE. g., it was possible to render a template with `hass-cli template bad-template.j2 --local` that contained entries like\n\n````j2\n{%- set b = environ.__globals__[\u0027__builtins__\u0027] -%}\n{%- set os = b[\u0027__import__\u0027](\u0027os\u0027) -%}\n{%- set bio = b[\u0027__import__\u0027](\u0027builtins\u0027) -%}\n...\n````\n\nor other malicious Jinja2 expressions. This can lead to arbitrary code execution on the local machine.\n\nIn a two step process an adversary could trick/convince an user to download third-party templates which contain harmful code (e. g., perform data manipulation or establish a remote shell) then to render those templates unchecked/reviewed/verified with `--local`. \n\nThe issue only affect the local machine and not a remote Home Assistant instance. It also requires user interventions.\n\n### Patches\n\n1.0.0 uses `ImmutableSandboxedEnvironment` and restricts the usage of environment variables.\n\n### Workarounds\n\nEvaluate the Jninja2 templates manually or tool-based before rendering with `hass-cli`.",
"id": "GHSA-33qf-q99x-wpm8",
"modified": "2026-04-27T16:15:58Z",
"published": "2026-04-16T21:28:39Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/home-assistant-ecosystem/home-assistant-cli/security/advisories/GHSA-33qf-q99x-wpm8"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-40602"
},
{
"type": "WEB",
"url": "https://github.com/home-assistant-ecosystem/home-assistant-cli/pull/453"
},
{
"type": "PACKAGE",
"url": "https://github.com/home-assistant-ecosystem/home-assistant-cli"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:H/PR:H/UI:R/S:U/C:H/I:H/A:N",
"type": "CVSS_V3"
}
],
"summary": "Home Assistant Command-line Interface: Handling of user-supplied Jinja2 templates"
}
GHSA-33QG-R99W-M2X7
Vulnerability from github – Published: 2022-05-01 18:31 – Updated: 2022-05-01 18:31Multiple PHP remote file inclusion vulnerabilities in phpWCMS XT 0.0.7 BETA and earlier allow remote attackers to execute arbitrary PHP code via a URL in the HTML_MENU_DirPath parameter to (1) config_HTML_MENU.php and (2) config_PHPLM.php in phpwcms_template/inc_script/frontend_render/navigation/.
{
"affected": [],
"aliases": [
"CVE-2007-5185"
],
"database_specific": {
"cwe_ids": [
"CWE-94"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2007-10-03T14:17:00Z",
"severity": "MODERATE"
},
"details": "Multiple PHP remote file inclusion vulnerabilities in phpWCMS XT 0.0.7 BETA and earlier allow remote attackers to execute arbitrary PHP code via a URL in the HTML_MENU_DirPath parameter to (1) config_HTML_MENU.php and (2) config_PHPLM.php in phpwcms_template/inc_script/frontend_render/navigation/.",
"id": "GHSA-33qg-r99w-m2x7",
"modified": "2022-05-01T18:31:02Z",
"published": "2022-05-01T18:31:02Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2007-5185"
},
{
"type": "WEB",
"url": "https://exchange.xforce.ibmcloud.com/vulnerabilities/36905"
},
{
"type": "WEB",
"url": "https://www.exploit-db.com/exploits/4477"
},
{
"type": "WEB",
"url": "http://osvdb.org/38591"
},
{
"type": "WEB",
"url": "http://osvdb.org/38592"
},
{
"type": "WEB",
"url": "http://www.securityfocus.com/bid/25879"
},
{
"type": "WEB",
"url": "http://www.vupen.com/english/advisories/2007/3332"
}
],
"schema_version": "1.4.0",
"severity": []
}
GHSA-33R5-HF6M-MC27
Vulnerability from github – Published: 2024-05-06 15:30 – Updated: 2024-07-03 18:39An issue in Library System using PHP/MySQli with Source Code V1.0 allows a remote attacker to execute arbitrary code via the _FAILE variable in the student_edit_photo.php component.
{
"affected": [],
"aliases": [
"CVE-2024-33294"
],
"database_specific": {
"cwe_ids": [
"CWE-94"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-05-06T15:15:23Z",
"severity": "CRITICAL"
},
"details": "An issue in Library System using PHP/MySQli with Source Code V1.0 allows a remote attacker to execute arbitrary code via the _FAILE variable in the student_edit_photo.php component.",
"id": "GHSA-33r5-hf6m-mc27",
"modified": "2024-07-03T18:39:08Z",
"published": "2024-05-06T15:30:39Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-33294"
},
{
"type": "WEB",
"url": "https://github.com/CveSecLook/cve/issues/16"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-33V4-22CQ-M9G2
Vulnerability from github – Published: 2024-10-26 12:30 – Updated: 2024-11-25 21:30The The Uix Shortcodes – Compatible with Gutenberg plugin for WordPress is vulnerable to arbitrary shortcode execution in all versions up to, and including, 1.9.9. This is due to the software allowing users to execute an action that does not properly validate a value before running do_shortcode. This makes it possible for unauthenticated attackers to execute arbitrary shortcodes.
{
"affected": [],
"aliases": [
"CVE-2024-9772"
],
"database_specific": {
"cwe_ids": [
"CWE-94"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-10-26T10:15:10Z",
"severity": "HIGH"
},
"details": "The The Uix Shortcodes \u2013 Compatible with Gutenberg plugin for WordPress is vulnerable to arbitrary shortcode execution in all versions up to, and including, 1.9.9. This is due to the software allowing users to execute an action that does not properly validate a value before running do_shortcode. This makes it possible for unauthenticated attackers to execute arbitrary shortcodes.",
"id": "GHSA-33v4-22cq-m9g2",
"modified": "2024-11-25T21:30:48Z",
"published": "2024-10-26T12:30:43Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-9772"
},
{
"type": "WEB",
"url": "https://plugins.trac.wordpress.org/browser/uix-shortcodes/trunk/shortcodes/templates/default/frontpage-init.php#L9"
},
{
"type": "WEB",
"url": "https://wordpress.org/plugins/uix-shortcodes/#developers"
},
{
"type": "WEB",
"url": "https://www.wordfence.com/threat-intel/vulnerabilities/id/3000758d-68e0-46a6-aef0-e2407a828168?source=cve"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L",
"type": "CVSS_V3"
}
]
}
GHSA-33WC-423W-3V87
Vulnerability from github – Published: 2024-07-29 18:30 – Updated: 2024-07-29 18:30Versions of Delphix Engine prior to Release 25.0.0.0 contain a flaw which results in Remote Code Execution (RCE).
{
"affected": [],
"aliases": [
"CVE-2024-6726"
],
"database_specific": {
"cwe_ids": [
"CWE-94"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-07-29T18:15:12Z",
"severity": "HIGH"
},
"details": "Versions of Delphix Engine prior to Release 25.0.0.0 contain a flaw which results in Remote Code Execution (RCE).",
"id": "GHSA-33wc-423w-3v87",
"modified": "2024-07-29T18:30:44Z",
"published": "2024-07-29T18:30:44Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-6726"
},
{
"type": "WEB",
"url": "https://portal.perforce.com/s/detail/a91PA000001SUDtYAO"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-342V-J2X2-9WRP
Vulnerability from github – Published: 2022-05-17 01:56 – Updated: 2022-05-17 01:56PHP remote file inclusion vulnerability in tools/phpmailer/class.phpmailer.php in PHP Classifieds 7.3 allows remote attackers to execute arbitrary PHP code via a URL in the lang_path parameter.
{
"affected": [],
"aliases": [
"CVE-2010-4914"
],
"database_specific": {
"cwe_ids": [
"CWE-94"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2011-10-08T10:55:00Z",
"severity": "HIGH"
},
"details": "PHP remote file inclusion vulnerability in tools/phpmailer/class.phpmailer.php in PHP Classifieds 7.3 allows remote attackers to execute arbitrary PHP code via a URL in the lang_path parameter.",
"id": "GHSA-342v-j2x2-9wrp",
"modified": "2022-05-17T01:56:39Z",
"published": "2022-05-17T01:56:39Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2010-4914"
},
{
"type": "WEB",
"url": "https://exchange.xforce.ibmcloud.com/vulnerabilities/61603"
},
{
"type": "WEB",
"url": "http://www.exploit-db.com/exploits/14893"
}
],
"schema_version": "1.4.0",
"severity": []
}
GHSA-3448-7XQ8-P7M9
Vulnerability from github – Published: 2022-05-01 18:33 – Updated: 2022-05-01 18:33PHP remote file inclusion vulnerability in admin.color.php in the com_colorlab (aka com_color) 1.0 component for Joomla! allows remote attackers to execute arbitrary PHP code via a URL in the mosConfig_live_site parameter.
{
"affected": [],
"aliases": [
"CVE-2007-5451"
],
"database_specific": {
"cwe_ids": [
"CWE-94"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2007-10-14T18:17:00Z",
"severity": "MODERATE"
},
"details": "PHP remote file inclusion vulnerability in admin.color.php in the com_colorlab (aka com_color) 1.0 component for Joomla! allows remote attackers to execute arbitrary PHP code via a URL in the mosConfig_live_site parameter.",
"id": "GHSA-3448-7xq8-p7m9",
"modified": "2022-05-01T18:33:32Z",
"published": "2022-05-01T18:33:32Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2007-5451"
},
{
"type": "WEB",
"url": "https://www.exploit-db.com/exploits/4524"
},
{
"type": "WEB",
"url": "http://osvdb.org/40609"
},
{
"type": "WEB",
"url": "http://www.securityfocus.com/bid/26059"
}
],
"schema_version": "1.4.0",
"severity": []
}
Mitigation
Strategy: Refactoring
Refactor your program so that you do not have to dynamically generate code.
Mitigation
- Run your code in a "jail" or similar sandbox environment that enforces strict boundaries between the process and the operating system. This may effectively restrict which code can be executed by your product.
- Examples include the Unix chroot jail and AppArmor. In general, managed code may provide some protection.
- This may not be a feasible solution, and it only limits the impact to the operating system; the rest of your application may still be subject to compromise.
- Be careful to avoid CWE-243 and other weaknesses related to jails.
Mitigation MIT-5
Strategy: Input Validation
- Assume all input is malicious. Use an "accept known good" input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.
- When performing input validation, consider all potentially relevant properties, including length, type of input, the full range of acceptable values, missing or extra inputs, syntax, consistency across related fields, and conformance to business rules. As an example of business rule logic, "boat" may be syntactically valid because it only contains alphanumeric characters, but it is not valid if the input is only expected to contain colors such as "red" or "blue."
- Do not rely exclusively on looking for malicious or malformed inputs. This is likely to miss at least one undesirable input, especially if the code's environment changes. This can give attackers enough room to bypass the intended validation. However, denylists can be useful for detecting potential attacks or determining which inputs are so malformed that they should be rejected outright.
- To reduce the likelihood of code injection, use stringent allowlists that limit which constructs are allowed. If you are dynamically constructing code that invokes a function, then verifying that the input is alphanumeric might be insufficient. An attacker might still be able to reference a dangerous function that you did not intend to allow, such as system(), exec(), or exit().
Mitigation
Use dynamic tools and techniques that interact with the product using large test suites with many diverse inputs, such as fuzz testing (fuzzing), robustness testing, and fault injection. The product's operation may slow down, but it should not become unstable, crash, or generate incorrect results.
Mitigation MIT-32
Strategy: Compilation or Build Hardening
Run the code in an environment that performs automatic taint propagation and prevents any command execution that uses tainted variables, such as Perl's "-T" switch. This will force the program to perform validation steps that remove the taint, although you must be careful to correctly validate your inputs so that you do not accidentally mark dangerous inputs as untainted (see CWE-183 and CWE-184).
Mitigation MIT-32
Strategy: Environment Hardening
Run the code in an environment that performs automatic taint propagation and prevents any command execution that uses tainted variables, such as Perl's "-T" switch. This will force the program to perform validation steps that remove the taint, although you must be careful to correctly validate your inputs so that you do not accidentally mark dangerous inputs as untainted (see CWE-183 and CWE-184).
Mitigation
For Python programs, it is frequently encouraged to use the ast.literal_eval() function instead of eval, since it is intentionally designed to avoid executing code. However, an adversary could still cause excessive memory or stack consumption via deeply nested structures [REF-1372], so the python documentation discourages use of ast.literal_eval() on untrusted data [REF-1373].
CAPEC-242: Code Injection
An adversary exploits a weakness in input validation on the target to inject new code into that which is currently executing. This differs from code inclusion in that code inclusion involves the addition or replacement of a reference to a code file, which is subsequently loaded by the target and used as part of the code of some application.
CAPEC-35: Leverage Executable Code in Non-Executable Files
An attack of this type exploits a system's trust in configuration and resource files. When the executable loads the resource (such as an image file or configuration file) the attacker has modified the file to either execute malicious code directly or manipulate the target process (e.g. application server) to execute based on the malicious configuration parameters. Since systems are increasingly interrelated mashing up resources from local and remote sources the possibility of this attack occurring is high.
CAPEC-77: Manipulating User-Controlled Variables
This attack targets user controlled variables (DEBUG=1, PHP Globals, and So Forth). An adversary can override variables leveraging user-supplied, untrusted query variables directly used on the application server without any data sanitization. In extreme cases, the adversary can change variables controlling the business logic of the application. For instance, in languages like PHP, a number of poorly set default configurations may allow the user to override variables.