Common Weakness Enumeration

CWE-77

Allowed-with-Review

Improper Neutralization of Special Elements used in a Command ('Command Injection')

Abstraction: Class · Status: Draft

The product constructs all or part of a command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended command when it is sent to a downstream component.

5381 vulnerabilities reference this CWE, most recent first.

GHSA-XC89-PRGW-P5XC

Vulnerability from github – Published: 2025-08-26 00:31 – Updated: 2025-08-26 00:31
VLAI
Details

D-Link DSL-7740C with firmware DSL7740C.V6.TR069.20211230 was discovered to contain a command injection vulnerability via the ping6 function.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2025-29523"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-77"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2025-08-25T16:15:30Z",
    "severity": "HIGH"
  },
  "details": "D-Link DSL-7740C with firmware DSL7740C.V6.TR069.20211230 was discovered to contain a command injection vulnerability via the ping6 function.",
  "id": "GHSA-xc89-prgw-p5xc",
  "modified": "2025-08-26T00:31:14Z",
  "published": "2025-08-26T00:31:13Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-29523"
    },
    {
      "type": "WEB",
      "url": "https://gist.github.com/stevenyu113228/6dbc5eb4311390e4e9a8f89fdb659406"
    },
    {
      "type": "WEB",
      "url": "https://www.dlink.com/en/security-bulletin"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-XCGP-R7R8-2HC9

Vulnerability from github – Published: 2024-03-27 18:32 – Updated: 2024-04-16 15:50
VLAI
Summary
Gradio's CI vulnerable to Command Injection
Details

A command injection vulnerability exists in the deploy+test-visual.yml workflow of the gradio-app/gradio repository, due to improper neutralization of special elements used in a command. This vulnerability allows attackers to execute unauthorized commands, potentially leading to unauthorized modification of the base repository or secrets exfiltration. The issue arises from the unsafe handling of GitHub context information within a an action definition which is evaluated and substituted before script execution. Remediation involves setting untrusted input values to intermediate environment variables to prevent direct influence on script generation.

Show details on source website

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "gradio"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.18.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2024-1540"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-77"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2024-03-27T21:56:42Z",
    "nvd_published_at": "2024-03-27T16:15:09Z",
    "severity": "HIGH"
  },
  "details": "A command injection vulnerability exists in the deploy+test-visual.yml workflow of the gradio-app/gradio repository, due to improper neutralization of special elements used in a command. This vulnerability allows attackers to execute unauthorized commands, potentially leading to unauthorized modification of the base repository or secrets exfiltration. The issue arises from the unsafe handling of GitHub context information within a an action definition which is evaluated and substituted before script execution. Remediation involves setting untrusted input values to intermediate environment variables to prevent direct influence on script generation.",
  "id": "GHSA-xcgp-r7r8-2hc9",
  "modified": "2024-04-16T15:50:40Z",
  "published": "2024-03-27T18:32:38Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-1540"
    },
    {
      "type": "WEB",
      "url": "https://github.com/gradio-app/gradio/commit/d56bb28df80d8db1f33e4acf4f6b2c4f87cb8b28"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/gradio-app/gradio"
    },
    {
      "type": "WEB",
      "url": "https://huntr.com/bounties/0e39e974-9a66-476f-91f5-3f37abb03d77"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:L",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Gradio\u0027s CI vulnerable to Command Injection",
  "withdrawn": "2024-03-27T21:57:19Z"
}

GHSA-XCR8-Q8RV-J3C5

Vulnerability from github – Published: 2023-05-12 00:30 – Updated: 2024-04-04 04:03
VLAI
Details

Motorola CX2L Router 1.0.1 was discovered to contain a command injection vulnerability via the smartqos_priority_devices parameter.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2023-31530"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-77"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2023-05-11T22:15:11Z",
    "severity": "HIGH"
  },
  "details": "Motorola CX2L Router 1.0.1 was discovered to contain a command injection vulnerability via the smartqos_priority_devices parameter.",
  "id": "GHSA-xcr8-q8rv-j3c5",
  "modified": "2024-04-04T04:03:32Z",
  "published": "2023-05-12T00:30:18Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-31530"
    },
    {
      "type": "WEB",
      "url": "https://github.com/leetsun/IoT/tree/main/Motorola-CX2L/CI4"
    }
  ],
  "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-XF2V-W36Q-24WF

Vulnerability from github – Published: 2026-07-12 09:31 – Updated: 2026-07-12 09:31
VLAI
Details

A vulnerability has been found in TRENDnet TEW-821DAP 1.11B03. This affects the function sub_42026C of the file /goform/tools_ddns of the component Firmware Update Handler. Such manipulation of the argument hostname/username/password leads to os command injection. The attack can be launched remotely. The vendor explains: "We are unable to confirm the existence of the vulnerabilities for (...) TEW-821DAP (v1.0R) as these items have been EOL. " This vulnerability only affects products that are no longer supported by the maintainer.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2026-15486"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-77"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-07-12T09:16:38Z",
    "severity": "MODERATE"
  },
  "details": "A vulnerability has been found in TRENDnet TEW-821DAP 1.11B03. This affects the function sub_42026C of the file /goform/tools_ddns of the component Firmware Update Handler. Such manipulation of the argument hostname/username/password leads to os command injection. The attack can be launched remotely. The vendor explains: \"We are unable to confirm the existence of the vulnerabilities for (...) TEW-821DAP (v1.0R) as these items have been EOL. \" This vulnerability only affects products that are no longer supported by the maintainer.",
  "id": "GHSA-xf2v-w36q-24wf",
  "modified": "2026-07-12T09:31:46Z",
  "published": "2026-07-12T09:31:46Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-15486"
    },
    {
      "type": "WEB",
      "url": "https://github.com/IOTRes/IOT_Firmware_Update/blob/main/Trendnet/TEW-821DAP_CI4.md"
    },
    {
      "type": "WEB",
      "url": "https://vuldb.com/cve/CVE-2026-15486"
    },
    {
      "type": "WEB",
      "url": "https://vuldb.com/submit/842383"
    },
    {
      "type": "WEB",
      "url": "https://vuldb.com/vuln/377793"
    },
    {
      "type": "WEB",
      "url": "https://vuldb.com/vuln/377793/cti"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}

GHSA-XF4J-P5GP-H24H

Vulnerability from github – Published: 2022-05-17 03:18 – Updated: 2022-05-17 03:18
VLAI
Details

An issue was discovered in Pivotal Greenplum before 4.3.10.0. Creation of external tables using GPHDFS protocol has a vulnerability whereby arbitrary commands can be injected into the system. In order to exploit this vulnerability the user must have superuser 'gpadmin' access to the system or have been granted GPHDFS protocol permissions in order to create a GPHDFS external table.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2016-6656"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-77"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2016-12-16T09:59:00Z",
    "severity": "HIGH"
  },
  "details": "An issue was discovered in Pivotal Greenplum before 4.3.10.0. Creation of external tables using GPHDFS protocol has a vulnerability whereby arbitrary commands can be injected into the system. In order to exploit this vulnerability the user must have superuser \u0027gpadmin\u0027 access to the system or have been granted GPHDFS protocol permissions in order to create a GPHDFS external table.",
  "id": "GHSA-xf4j-p5gp-h24h",
  "modified": "2022-05-17T03:18:22Z",
  "published": "2022-05-17T03:18:22Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2016-6656"
    },
    {
      "type": "WEB",
      "url": "https://pivotal.io/security/cve-2016-6656"
    },
    {
      "type": "WEB",
      "url": "http://www.securityfocus.com/bid/94954"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.0/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-XF6F-94PC-55VC

Vulnerability from github – Published: 2024-02-08 06:30 – Updated: 2024-09-05 15:33
VLAI
Details

Zentao v18.0 to v18.10 was discovered to contain a remote code execution (RCE) vulnerability via the checkConnection method of /app/zentao/module/repo/model.php.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2024-24216"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-77"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2024-02-08T06:15:51Z",
    "severity": "CRITICAL"
  },
  "details": "Zentao v18.0 to v18.10 was discovered to contain a remote code execution (RCE) vulnerability via the checkConnection method of /app/zentao/module/repo/model.php.",
  "id": "GHSA-xf6f-94pc-55vc",
  "modified": "2024-09-05T15:33:32Z",
  "published": "2024-02-08T06:30:24Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-24216"
    },
    {
      "type": "WEB",
      "url": "https://github.com/easysoft/zentaopms/issues/133"
    },
    {
      "type": "WEB",
      "url": "https://github.com/l3s10n/ZenTaoPMS_RCE"
    }
  ],
  "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:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-XF6G-WJR6-2444

Vulnerability from github – Published: 2022-03-19 00:00 – Updated: 2022-03-26 00:00
VLAI
Details

Tenda AC9 v15.03.2.21 was discovered to contain a stack overflow via the deviceId parameter in the saveparentcontrolinfo function.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2022-25428"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-77"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2022-03-18T21:15:00Z",
    "severity": "CRITICAL"
  },
  "details": "Tenda AC9 v15.03.2.21 was discovered to contain a stack overflow via the deviceId parameter in the saveparentcontrolinfo function.",
  "id": "GHSA-xf6g-wjr6-2444",
  "modified": "2022-03-26T00:00:42Z",
  "published": "2022-03-19T00:00:49Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2022-25428"
    },
    {
      "type": "WEB",
      "url": "https://github.com/EPhaha/IOT_vuln/tree/main/Tenda/AC9/3"
    }
  ],
  "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:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-XF77-XQPR-2GH9

Vulnerability from github – Published: 2022-05-24 17:44 – Updated: 2022-06-29 00:00
VLAI
Details

** DISPUTED ** MikroTik RouterOS 6.47.9 allows remote authenticated ftp users to create or overwrite arbitrary .rsc files via the /export command. NOTE: the vendor's position is that this is intended behavior because of how user policies work.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2021-27221"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-77"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2021-03-19T03:15:00Z",
    "severity": "HIGH"
  },
  "details": "** DISPUTED ** MikroTik RouterOS 6.47.9 allows remote authenticated ftp users to create or overwrite arbitrary .rsc files via the /export command. NOTE: the vendor\u0027s position is that this is intended behavior because of how user policies work.",
  "id": "GHSA-xf77-xqpr-2gh9",
  "modified": "2022-06-29T00:00:49Z",
  "published": "2022-05-24T17:44:55Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-27221"
    },
    {
      "type": "WEB",
      "url": "https://onovy.medium.com/routeros-user-with-just-ftp-policy-can-write-to-filesystem-cve-2021-27221-e3e45d780dfe"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-XFFF-M68H-GJF7

Vulnerability from github – Published: 2022-09-17 00:00 – Updated: 2022-09-18 00:00
VLAI
Details

TOTOLINK T6 V4.1.5cu.709_B20210518 is vulnerable to command injection via cstecgi.cgi

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2022-38828"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-77"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2022-09-16T15:15:00Z",
    "severity": "CRITICAL"
  },
  "details": "TOTOLINK T6 V4.1.5cu.709_B20210518 is vulnerable to command injection via cstecgi.cgi",
  "id": "GHSA-xfff-m68h-gjf7",
  "modified": "2022-09-18T00:00:32Z",
  "published": "2022-09-17T00:00:36Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2022-38828"
    },
    {
      "type": "WEB",
      "url": "https://github.com/whiter6666/CVE/blob/main/TOTOLINK_T6_V3/setWiFiWpsStart_1.md"
    }
  ],
  "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:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-XFG4-45F5-2G88

Vulnerability from github – Published: 2024-05-16 15:31 – Updated: 2024-05-16 15:31
VLAI
Details

A vulnerability in the ConfD CLI and the Cisco Crosswork Network Services Orchestrator CLI could allow an authenticated, low-privileged, local attacker to read and write arbitrary files as root on the underlying operating system.

This vulnerability is due to improper authorization enforcement when specific CLI commands are used. An attacker could exploit this vulnerability by executing an affected CLI command with crafted arguments. A successful exploit could allow the attacker to read or write arbitrary files on the underlying operating system with the privileges of the root user.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2024-20326"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-77",
      "CWE-78"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2024-05-16T14:15:08Z",
    "severity": "HIGH"
  },
  "details": "A vulnerability in the ConfD CLI and the Cisco  Crosswork Network Services Orchestrator CLI could allow an authenticated, low-privileged, local attacker to read and write arbitrary files as root on the underlying operating system.\n\n\nThis vulnerability is due to improper authorization enforcement when specific CLI commands are used. An attacker could exploit this vulnerability by executing an affected CLI command with crafted arguments. A successful exploit could allow the attacker to read or write arbitrary files on the underlying operating system with the privileges of the root user.",
  "id": "GHSA-xfg4-45f5-2g88",
  "modified": "2024-05-16T15:31:37Z",
  "published": "2024-05-16T15:31:37Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-20326"
    },
    {
      "type": "WEB",
      "url": "https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-cnfd-rwpesc-ZAOufyx8"
    },
    {
      "type": "WEB",
      "url": "https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-nso-rwpesc-qrQGnh3f"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

Mitigation
Architecture and Design

If at all possible, use library calls rather than external processes to recreate the desired functionality.

Mitigation
Implementation

If possible, ensure that all external commands called from the program are statically created.

Mitigation MIT-5
Implementation

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.
Mitigation
Operation

Run time: Run time policy enforcement may be used in an allowlist fashion to prevent use of any non-sanctioned commands.

Mitigation
System Configuration

Assign permissions that prevent the user from accessing/opening privileged files.

CAPEC-136: LDAP Injection

An attacker manipulates or crafts an LDAP query for the purpose of undermining the security of the target. Some applications use user input to create LDAP queries that are processed by an LDAP server. For example, a user might provide their username during authentication and the username might be inserted in an LDAP query during the authentication process. An attacker could use this input to inject additional commands into an LDAP query that could disclose sensitive information. For example, entering a * in the aforementioned query might return information about all users on the system. This attack is very similar to an SQL injection attack in that it manipulates a query to gather additional information or coerce a particular return value.

CAPEC-15: Command Delimiters

An attack of this type exploits a programs' vulnerabilities that allows an attacker's commands to be concatenated onto a legitimate command with the intent of targeting other resources such as the file system or database. The system that uses a filter or denylist input validation, as opposed to allowlist validation is vulnerable to an attacker who predicts delimiters (or combinations of delimiters) not present in the filter or denylist. As with other injection attacks, the attacker uses the command delimiter payload as an entry point to tunnel through the application and activate additional attacks through SQL queries, shell commands, network scanning, and so on.

CAPEC-183: IMAP/SMTP Command Injection

An adversary exploits weaknesses in input validation on web-mail servers to execute commands on the IMAP/SMTP server. Web-mail servers often sit between the Internet and the IMAP or SMTP mail server. User requests are received by the web-mail servers which then query the back-end mail server for the requested information and return this response to the user. In an IMAP/SMTP command injection attack, mail-server commands are embedded in parts of the request sent to the web-mail server. If the web-mail server fails to adequately sanitize these requests, these commands are then sent to the back-end mail server when it is queried by the web-mail server, where the commands are then executed. This attack can be especially dangerous since administrators may assume that the back-end server is protected against direct Internet access and therefore may not secure it adequately against the execution of malicious commands.

CAPEC-248: Command Injection

An adversary looking to execute a command of their choosing, injects new items into an existing command thus modifying interpretation away from what was intended. Commands in this context are often standalone strings that are interpreted by a downstream component and cause specific responses. This type of attack is possible when untrusted values are used to build these command strings. Weaknesses in input validation or command construction can enable the attack and lead to successful exploitation.

CAPEC-40: Manipulating Writeable Terminal Devices

This attack exploits terminal devices that allow themselves to be written to by other users. The attacker sends command strings to the target terminal device hoping that the target user will hit enter and thereby execute the malicious command with their privileges. The attacker can send the results (such as copying /etc/passwd) to a known directory and collect once the attack has succeeded.

CAPEC-43: Exploiting Multiple Input Interpretation Layers

An attacker supplies the target software with input data that contains sequences of special characters designed to bypass input validation logic. This exploit relies on the target making multiples passes over the input data and processing a "layer" of special characters with each pass. In this manner, the attacker can disguise input that would otherwise be rejected as invalid by concealing it with layers of special/escape characters that are stripped off by subsequent processing steps. The goal is to first discover cases where the input validation layer executes before one or more parsing layers. That is, user input may go through the following logic in an application: <parser1> --> <input validator> --> <parser2>. In such cases, the attacker will need to provide input that will pass through the input validator, but after passing through parser2, will be converted into something that the input validator was supposed to stop.

CAPEC-75: Manipulating Writeable Configuration Files

Generally these are manually edited files that are not in the preview of the system administrators, any ability on the attackers' behalf to modify these files, for example in a CVS repository, gives unauthorized access directly to the application, the same as authorized users.

CAPEC-76: Manipulating Web Input to File System Calls

An attacker manipulates inputs to the target software which the target software passes to file system calls in the OS. The goal is to gain access to, and perhaps modify, areas of the file system that the target software did not intend to be accessible.