CWE-77
Allowed-with-ReviewImproper 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.
5839 vulnerabilities reference this CWE, most recent first.
GHSA-FPR8-4WVX-J9Q3
Vulnerability from github – Published: 2023-10-14 06:30 – Updated: 2023-10-17 02:11All versions of the package node-qpdf are vulnerable to Command Injection such that the package-exported method encrypt() fails to sanitize its parameter input, which later flows into a sensitive command execution API. As a result, attackers may inject malicious commands once they can specify the input pdf file path.
{
"affected": [
{
"package": {
"ecosystem": "npm",
"name": "node-qpdf"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"last_affected": "1.0.3"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2023-26155"
],
"database_specific": {
"cwe_ids": [
"CWE-77",
"CWE-94"
],
"github_reviewed": true,
"github_reviewed_at": "2023-10-17T02:11:20Z",
"nvd_published_at": "2023-10-14T05:15:55Z",
"severity": "HIGH"
},
"details": "All versions of the package node-qpdf are vulnerable to Command Injection such that the package-exported method encrypt() fails to sanitize its parameter input, which later flows into a sensitive command execution API. As a result, attackers may inject malicious commands once they can specify the input pdf file path.",
"id": "GHSA-fpr8-4wvx-j9q3",
"modified": "2023-10-17T02:11:20Z",
"published": "2023-10-14T06:30:54Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2023-26155"
},
{
"type": "WEB",
"url": "https://github.com/nrhirani/node-qpdf/issues/23"
},
{
"type": "PACKAGE",
"url": "https://github.com/nrhirani/node-qpdf"
},
{
"type": "WEB",
"url": "https://security.snyk.io/vuln/SNYK-JS-NODEQPDF-5747918"
}
],
"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"
}
],
"summary": "node-qpdf vulnerable to command injection "
}
GHSA-FQ43-FXRW-VJRH
Vulnerability from github – Published: 2023-08-22 21:30 – Updated: 2024-04-04 07:06Memcached 1.6.0 before 1.6.3 allows remote attackers to cause a denial of service (daemon crash) via a crafted meta command.
{
"affected": [],
"aliases": [
"CVE-2020-22570"
],
"database_specific": {
"cwe_ids": [
"CWE-77"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2023-08-22T19:16:19Z",
"severity": "HIGH"
},
"details": "Memcached 1.6.0 before 1.6.3 allows remote attackers to cause a denial of service (daemon crash) via a crafted meta command.",
"id": "GHSA-fq43-fxrw-vjrh",
"modified": "2024-04-04T07:06:15Z",
"published": "2023-08-22T21:30:25Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2020-22570"
},
{
"type": "WEB",
"url": "https://github.com/memcached/memcached/issues/636"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-FQ6H-WGJW-FFM5
Vulnerability from github – Published: 2024-12-03 21:31 – Updated: 2024-12-03 21:31A vulnerability in the ClearPass Policy Manager web-based management interface allows remote authenticated users to run arbitrary commands on the underlying host. Successful exploit could allow an attacker to execute arbitrary commands as a lower privileged user on the underlying operating system.
{
"affected": [],
"aliases": [
"CVE-2024-53672"
],
"database_specific": {
"cwe_ids": [
"CWE-77"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-12-03T21:15:07Z",
"severity": "MODERATE"
},
"details": "A vulnerability in the ClearPass Policy Manager web-based management interface allows remote authenticated users to run arbitrary commands on the underlying host. Successful exploit could allow an attacker to execute arbitrary commands as a lower privileged user on the underlying operating system.",
"id": "GHSA-fq6h-wgjw-ffm5",
"modified": "2024-12-03T21:31:22Z",
"published": "2024-12-03T21:31:22Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-53672"
},
{
"type": "WEB",
"url": "https://support.hpe.com/hpesc/public/docDisplay?docId=hpesbnw04761en_us\u0026docLocale=en_US"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:L",
"type": "CVSS_V3"
}
]
}
GHSA-FQ6P-2QGQ-54M8
Vulnerability from github – Published: 2025-09-26 18:31 – Updated: 2025-11-19 15:31Notepad++ v8.8.3 has a DLL hijacking vulnerability, which can replace the original DLL file to execute malicious code.
{
"affected": [],
"aliases": [
"CVE-2025-56383"
],
"database_specific": {
"cwe_ids": [
"CWE-427",
"CWE-77"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-09-26T18:15:36Z",
"severity": "MODERATE"
},
"details": "Notepad++ v8.8.3 has a DLL hijacking vulnerability, which can replace the original DLL file to execute malicious code.",
"id": "GHSA-fq6p-2qgq-54m8",
"modified": "2025-11-19T15:31:32Z",
"published": "2025-09-26T18:31:23Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-56383"
},
{
"type": "WEB",
"url": "https://github.com/zer0t0/CVE-2025-56383-Proof-of-Concept/issues/1"
},
{
"type": "WEB",
"url": "https://github.com/notepad-plus-plus/notepad-plus-plus"
},
{
"type": "WEB",
"url": "https://github.com/zer0t0/CVE-2025-56383-Proof-of-Concept"
},
{
"type": "WEB",
"url": "https://www.vicarius.io/vsociety/posts/cve-2025-56383-detect-notepad-vulnerability"
},
{
"type": "WEB",
"url": "https://www.vicarius.io/vsociety/posts/cve-2025-56383-mitigate-notepad-vulnerability"
}
],
"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:N",
"type": "CVSS_V3"
}
]
}
GHSA-FQ86-MQMV-XGG4
Vulnerability from github – Published: 2022-05-17 00:00 – Updated: 2022-05-26 00:01A authenticated remote command injection vulnerability was discovered in Aruba ClearPass Policy Manager version(s): 6.10.4 and below, 6.9.9 and below, 6.8.9-HF2 and below, 6.7.x and below. Aruba has released updates to ClearPass Policy Manager that address this security vulnerability.
{
"affected": [],
"aliases": [
"CVE-2022-23663"
],
"database_specific": {
"cwe_ids": [
"CWE-77",
"CWE-78"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2022-05-16T20:15:00Z",
"severity": "CRITICAL"
},
"details": "A authenticated remote command injection vulnerability was discovered in Aruba ClearPass Policy Manager version(s): 6.10.4 and below, 6.9.9 and below, 6.8.9-HF2 and below, 6.7.x and below. Aruba has released updates to ClearPass Policy Manager that address this security vulnerability.",
"id": "GHSA-fq86-mqmv-xgg4",
"modified": "2022-05-26T00:01:22Z",
"published": "2022-05-17T00:00:35Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2022-23663"
},
{
"type": "WEB",
"url": "https://www.arubanetworks.com/assets/alert/ARUBA-PSA-2022-007.txt"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-FQJR-2WGV-XW6R
Vulnerability from github – Published: 2026-09-24 21:32 – Updated: 2026-09-24 21:32A security flaw has been discovered in jhen0409 react-native-debugger up to 0.14.0. The impacted element is the function openDevTools of the file electron/window.js of the component Open in Editor Handler. The manipulation of the argument host results in os command injection. It is possible to launch the attack remotely. The exploit has been released to the public and may be used for attacks. The vendor was contacted early about this disclosure but did not respond in any way.
{
"affected": [],
"aliases": [
"CVE-2026-97366"
],
"database_specific": {
"cwe_ids": [
"CWE-77"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-09-24T21:18:58Z",
"severity": "LOW"
},
"details": "A security flaw has been discovered in jhen0409 react-native-debugger up to 0.14.0. The impacted element is the function openDevTools of the file electron/window.js of the component Open in Editor Handler. The manipulation of the argument host results in os command injection. It is possible to launch the attack remotely. The exploit has been released to the public and may be used for attacks. The vendor was contacted early about this disclosure but did not respond in any way.",
"id": "GHSA-fqjr-2wgv-xw6r",
"modified": "2026-09-24T21:32:51Z",
"published": "2026-09-24T21:32:51Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-97366"
},
{
"type": "WEB",
"url": "https://gist.github.com/Suuuuuzy/d25baf1973fd3c812277e02cde2243cc"
},
{
"type": "WEB",
"url": "https://vuldb.com/cve/CVE-2026-97366"
},
{
"type": "WEB",
"url": "https://vuldb.com/submit/909329"
},
{
"type": "WEB",
"url": "https://vuldb.com/vuln/409351"
},
{
"type": "WEB",
"url": "https://vuldb.com/vuln/409351/cti"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P/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-FQMX-HQ6J-36X9
Vulnerability from github – Published: 2023-08-16 21:31 – Updated: 2024-01-25 18:30A vulnerability in the web-based management interface of Cisco Expressway Series and Cisco TelePresence Video Communication Server (VCS) could allow an authenticated, remote attacker with read-write privileges on the application to perform a command injection attack that could result in remote code execution on an affected device.
This vulnerability is due to insufficient validation of user-supplied input. An attacker could exploit this vulnerability by sending a crafted request to the web-based management interface of an affected device. A successful exploit could allow the attacker to establish a remote shell with root privileges.
{
"affected": [],
"aliases": [
"CVE-2023-20209"
],
"database_specific": {
"cwe_ids": [
"CWE-77",
"CWE-94"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2023-08-16T21:15:09Z",
"severity": "HIGH"
},
"details": "A vulnerability in the web-based management interface of Cisco Expressway Series and Cisco TelePresence Video Communication Server (VCS) could allow an authenticated, remote attacker with read-write privileges on the application to perform a command injection attack that could result in remote code execution on an affected device.\n\n This vulnerability is due to insufficient validation of user-supplied input. An attacker could exploit this vulnerability by sending a crafted request to the web-based management interface of an affected device. A successful exploit could allow the attacker to establish a remote shell with root privileges.",
"id": "GHSA-fqmx-hq6j-36x9",
"modified": "2024-01-25T18:30:37Z",
"published": "2023-08-16T21:31:05Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2023-20209"
},
{
"type": "WEB",
"url": "https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-expressway-injection-X475EbTQ"
}
],
"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:N",
"type": "CVSS_V3"
}
]
}
GHSA-FQQ4-QR43-H5JQ
Vulnerability from github – Published: 2024-04-09 15:30 – Updated: 2024-04-09 15:30A command execution vulnerability exists in the tddpd enable_test_mode functionality of Tp-Link AC1350 Wireless MU-MIMO Gigabit Access Point (EAP225 V3) v5.1.0 Build 20220926 and Tp-Link N300 Wireless Access Point (EAP115 V4) v5.0.4 Build 20220216. A specially crafted series of network requests can lead to arbitrary command execution. An attacker can send a sequence of unauthenticated packets to trigger this vulnerability.This vulnerability impacts uclited on the EAP225(V3) 5.1.0 Build 20220926 of the AC1350 Wireless MU-MIMO Gigabit Access Point.
{
"affected": [],
"aliases": [
"CVE-2023-49133"
],
"database_specific": {
"cwe_ids": [
"CWE-77",
"CWE-829"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-04-09T15:15:29Z",
"severity": "HIGH"
},
"details": "A command execution vulnerability exists in the tddpd enable_test_mode functionality of Tp-Link AC1350 Wireless MU-MIMO Gigabit Access Point (EAP225 V3) v5.1.0 Build 20220926 and Tp-Link N300 Wireless Access Point (EAP115 V4) v5.0.4 Build 20220216. A specially crafted series of network requests can lead to arbitrary command execution. An attacker can send a sequence of unauthenticated packets to trigger this vulnerability.This vulnerability impacts `uclited` on the EAP225(V3) 5.1.0 Build 20220926 of the AC1350 Wireless MU-MIMO Gigabit Access Point.",
"id": "GHSA-fqq4-qr43-h5jq",
"modified": "2024-04-09T15:30:37Z",
"published": "2024-04-09T15:30:37Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2023-49133"
},
{
"type": "WEB",
"url": "https://talosintelligence.com/vulnerability_reports/TALOS-2023-1862"
},
{
"type": "WEB",
"url": "https://www.talosintelligence.com/vulnerability_reports/TALOS-2023-1862"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-FQWP-42Q8-85R2
Vulnerability from github – Published: 2022-05-13 01:46 – Updated: 2022-05-13 01:46An issue was discovered in certain Apple products. Safari before 11.0.2 is affected. The issue involves the "WebKit Web Inspector" component. It allows remote attackers to execute arbitrary code via special characters that trigger command injection.
{
"affected": [],
"aliases": [
"CVE-2017-7161"
],
"database_specific": {
"cwe_ids": [
"CWE-77"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2018-04-03T06:29:00Z",
"severity": "HIGH"
},
"details": "An issue was discovered in certain Apple products. Safari before 11.0.2 is affected. The issue involves the \"WebKit Web Inspector\" component. It allows remote attackers to execute arbitrary code via special characters that trigger command injection.",
"id": "GHSA-fqwp-42q8-85r2",
"modified": "2022-05-13T01:46:51Z",
"published": "2022-05-13T01:46:51Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2017-7161"
},
{
"type": "WEB",
"url": "https://support.apple.com/HT208324"
},
{
"type": "WEB",
"url": "https://usn.ubuntu.com/3551-1"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-FR39-X6RF-54C7
Vulnerability from github – Published: 2026-01-05 09:30 – Updated: 2026-01-05 09:30A vulnerability was determined in Tenda AC1206 15.03.06.23. Affected by this issue is the function formBehaviorManager of the file /goform/BehaviorManager of the component httpd. Executing a manipulation of the argument modulename/option/data/switch can lead to command injection. The attack can be launched remotely. The exploit has been publicly disclosed and may be utilized.
{
"affected": [],
"aliases": [
"CVE-2026-0581"
],
"database_specific": {
"cwe_ids": [
"CWE-74",
"CWE-77"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-01-05T09:15:54Z",
"severity": "MODERATE"
},
"details": "A vulnerability was determined in Tenda AC1206 15.03.06.23. Affected by this issue is the function formBehaviorManager of the file /goform/BehaviorManager of the component httpd. Executing a manipulation of the argument modulename/option/data/switch can lead to command injection. The attack can be launched remotely. The exploit has been publicly disclosed and may be utilized.",
"id": "GHSA-fr39-x6rf-54c7",
"modified": "2026-01-05T09:30:19Z",
"published": "2026-01-05T09:30:19Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-0581"
},
{
"type": "WEB",
"url": "https://github.com/ccc-iotsec/cve-/blob/Tenda/Tenda%20AC1206%E5%91%BD%E4%BB%A4%E6%B3%A8%E5%85%A5%E6%BC%8F%E6%B4%9E.md"
},
{
"type": "WEB",
"url": "https://vuldb.com/?ctiid.339473"
},
{
"type": "WEB",
"url": "https://vuldb.com/?id.339473"
},
{
"type": "WEB",
"url": "https://vuldb.com/?submit.731193"
},
{
"type": "WEB",
"url": "https://www.tenda.com.cn"
}
],
"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:P/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"
}
]
}
Mitigation
If at all possible, use library calls rather than external processes to recreate the desired functionality.
Mitigation
If possible, ensure that all external commands called from the program are statically created.
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.
Mitigation
Run time: Run time policy enforcement may be used in an allowlist fashion to prevent use of any non-sanctioned commands.
Mitigation
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.