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.
5385 vulnerabilities reference this CWE, most recent first.
GHSA-775F-24CQ-QG6P
Vulnerability from github – Published: 2025-03-20 12:32 – Updated: 2025-03-20 12:32In infiniflow/ragflow versions 0.12.0, the web_crawl function in document_app.py contains multiple vulnerabilities. The function does not filter URL parameters, allowing attackers to exploit Full Read SSRF by accessing internal network addresses and viewing their content through the generated PDF files. Additionally, the lack of restrictions on the file protocol enables Arbitrary File Read, allowing attackers to read server files. Furthermore, the use of an outdated Chromium headless version with --no-sandbox mode enabled makes the application susceptible to Remote Code Execution (RCE) via known Chromium v8 vulnerabilities. These issues are resolved in version 0.14.0.
{
"affected": [],
"aliases": [
"CVE-2024-12450"
],
"database_specific": {
"cwe_ids": [
"CWE-77",
"CWE-918"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-03-20T10:15:28Z",
"severity": "MODERATE"
},
"details": "In infiniflow/ragflow versions 0.12.0, the `web_crawl` function in `document_app.py` contains multiple vulnerabilities. The function does not filter URL parameters, allowing attackers to exploit Full Read SSRF by accessing internal network addresses and viewing their content through the generated PDF files. Additionally, the lack of restrictions on the file protocol enables Arbitrary File Read, allowing attackers to read server files. Furthermore, the use of an outdated Chromium headless version with --no-sandbox mode enabled makes the application susceptible to Remote Code Execution (RCE) via known Chromium v8 vulnerabilities. These issues are resolved in version 0.14.0.",
"id": "GHSA-775f-24cq-qg6p",
"modified": "2025-03-20T12:32:43Z",
"published": "2025-03-20T12:32:43Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-12450"
},
{
"type": "WEB",
"url": "https://github.com/infiniflow/ragflow/commit/3faae0b2c2f8a26233ee1442ba04874b3406f6e9"
},
{
"type": "WEB",
"url": "https://huntr.com/bounties/da06360c-87c3-4ba9-be67-29f6eff9d44a"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-775R-2987-9FPX
Vulnerability from github – Published: 2022-05-13 01:04 – Updated: 2022-05-13 01:04A Command Injection vulnerability in Schneider Electric homeLYnk Controller exists in all versions before 1.5.0.
{
"affected": [],
"aliases": [
"CVE-2017-7689"
],
"database_specific": {
"cwe_ids": [
"CWE-77"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2017-04-11T21:59:00Z",
"severity": "CRITICAL"
},
"details": "A Command Injection vulnerability in Schneider Electric homeLYnk Controller exists in all versions before 1.5.0.",
"id": "GHSA-775r-2987-9fpx",
"modified": "2022-05-13T01:04:04Z",
"published": "2022-05-13T01:04:04Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2017-7689"
},
{
"type": "WEB",
"url": "https://ics-cert.us-cert.gov/advisories/ICSA-17-019-01A"
},
{
"type": "WEB",
"url": "http://download.schneider-electric.com/files?p_Doc_Ref=SEVD-2017-052-02"
},
{
"type": "WEB",
"url": "http://www.securityfocus.com/bid/97585"
}
],
"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-7764-X48J-4RHP
Vulnerability from github – Published: 2023-03-25 21:30 – Updated: 2023-03-30 21:30** DISPUTED ** A vulnerability, which was classified as critical, has been found in Ubiquiti EdgeRouter X 2.0.9-hotfix.6. This issue affects some unknown processing of the component NAT Configuration Handler. The manipulation leads to command injection. The attack may be initiated remotely. The exploit has been disclosed to the public and may be used. The real existence of this vulnerability is still doubted at the moment. The identifier VDB-223301 was assigned to this vulnerability. NOTE: The vendor position is that post-authentication issues are not accepted as vulnerabilities.
{
"affected": [],
"aliases": [
"CVE-2023-1456"
],
"database_specific": {
"cwe_ids": [
"CWE-77"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2023-03-25T21:15:00Z",
"severity": "CRITICAL"
},
"details": "** DISPUTED ** A vulnerability, which was classified as critical, has been found in Ubiquiti EdgeRouter X 2.0.9-hotfix.6. This issue affects some unknown processing of the component NAT Configuration Handler. The manipulation leads to command injection. The attack may be initiated remotely. The exploit has been disclosed to the public and may be used. The real existence of this vulnerability is still doubted at the moment. The identifier VDB-223301 was assigned to this vulnerability. NOTE: The vendor position is that post-authentication issues are not accepted as vulnerabilities.",
"id": "GHSA-7764-x48j-4rhp",
"modified": "2023-03-30T21:30:23Z",
"published": "2023-03-25T21:30:18Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2023-1456"
},
{
"type": "WEB",
"url": "https://vuldb.com/?ctiid.223301"
},
{
"type": "WEB",
"url": "https://vuldb.com/?id.223301"
}
],
"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-7796-2CV5-G5F4
Vulnerability from github – Published: 2026-04-10 06:31 – Updated: 2026-04-10 06:31A vulnerability was identified in Totolink A7100RU 7.4cu.2313_b20191024. This affects the function setSyslogCfg of the file /cgi-bin/cstecgi.cgi of the component CGI Handler. Such manipulation of the argument enable leads to os command injection. It is possible to launch the attack remotely. The exploit is publicly available and might be used.
{
"affected": [],
"aliases": [
"CVE-2026-6025"
],
"database_specific": {
"cwe_ids": [
"CWE-77"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-04-10T06:16:07Z",
"severity": "HIGH"
},
"details": "A vulnerability was identified in Totolink A7100RU 7.4cu.2313_b20191024. This affects the function setSyslogCfg of the file /cgi-bin/cstecgi.cgi of the component CGI Handler. Such manipulation of the argument enable leads to os command injection. It is possible to launch the attack remotely. The exploit is publicly available and might be used.",
"id": "GHSA-7796-2cv5-g5f4",
"modified": "2026-04-10T06:31:38Z",
"published": "2026-04-10T06:31:38Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-6025"
},
{
"type": "WEB",
"url": "https://github.com/Litengzheng/vuldb_new/blob/main/A7100RU/vul_170/README.md"
},
{
"type": "WEB",
"url": "https://vuldb.com/submit/792046"
},
{
"type": "WEB",
"url": "https://vuldb.com/vuln/356601"
},
{
"type": "WEB",
"url": "https://vuldb.com/vuln/356601/cti"
},
{
"type": "WEB",
"url": "https://www.totolink.net"
}
],
"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"
},
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/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-77C7-PQ4R-6MCQ
Vulnerability from github – Published: 2026-06-09 06:31 – Updated: 2026-06-09 06:31Versions of the package degit before 2.8.6, from 3.0.0 and before 3.3.1 are vulnerable to Command Injection due to improper sanitisation of user input for git shell commands directly invoked with exec() method by _cloneWithGit() and fetchRefs() functions. An attacker can execute arbitrary operating system commands as the process user by supplying a specially crafted git repository name.
{
"affected": [],
"aliases": [
"CVE-2026-11572"
],
"database_specific": {
"cwe_ids": [
"CWE-77",
"CWE-78"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-06-09T06:16:53Z",
"severity": "HIGH"
},
"details": "Versions of the package degit before 2.8.6, from 3.0.0 and before 3.3.1 are vulnerable to Command Injection due to improper sanitisation of user input for git shell commands directly invoked with exec() method by _cloneWithGit() and fetchRefs() functions. An attacker can execute arbitrary operating system commands as the process user by supplying a specially crafted git repository name.",
"id": "GHSA-77c7-pq4r-6mcq",
"modified": "2026-06-09T06:31:59Z",
"published": "2026-06-09T06:31:59Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-11572"
},
{
"type": "WEB",
"url": "https://github.com/Rich-Harris/degit/commit/4ac99e4a4c3f53ca3b5c997bcd7542742ad0c443"
},
{
"type": "WEB",
"url": "https://github.com/Rich-Harris/degit/commit/d55bfd7cea79c0b387f69ec8477b6c34abf9f226"
},
{
"type": "WEB",
"url": "https://gist.github.com/badp3te/cf22a939eedbd3d8ade9123827d61639"
},
{
"type": "WEB",
"url": "https://security.snyk.io/vuln/SNYK-JS-DEGIT-17116207"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/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-77GM-C93F-MHJ7
Vulnerability from github – Published: 2025-08-07 21:31 – Updated: 2025-08-07 21:31Microsoft 365 Copilot BizChat Information Disclosure Vulnerability
{
"affected": [],
"aliases": [
"CVE-2025-53787"
],
"database_specific": {
"cwe_ids": [
"CWE-77"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-08-07T21:15:28Z",
"severity": "HIGH"
},
"details": "Microsoft 365 Copilot BizChat Information Disclosure Vulnerability",
"id": "GHSA-77gm-c93f-mhj7",
"modified": "2025-08-07T21:31:08Z",
"published": "2025-08-07T21:31:08Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-53787"
},
{
"type": "WEB",
"url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-53787"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-77GW-GG73-WPFG
Vulnerability from github – Published: 2025-04-30 15:30 – Updated: 2025-04-30 15:30A vulnerability was found in Netgear JWNR2000v2 1.0.0.11. It has been declared as critical. Affected by this vulnerability is the function cmd_wireless. The manipulation of the argument host leads to command injection. The attack can be launched remotely. The vendor was contacted early about this disclosure but did not respond in any way.
{
"affected": [],
"aliases": [
"CVE-2025-4121"
],
"database_specific": {
"cwe_ids": [
"CWE-74",
"CWE-77"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-04-30T14:15:31Z",
"severity": "MODERATE"
},
"details": "A vulnerability was found in Netgear JWNR2000v2 1.0.0.11. It has been declared as critical. Affected by this vulnerability is the function cmd_wireless. The manipulation of the argument host leads to command injection. The attack can be launched remotely. The vendor was contacted early about this disclosure but did not respond in any way.",
"id": "GHSA-77gw-gg73-wpfg",
"modified": "2025-04-30T15:30:49Z",
"published": "2025-04-30T15:30:49Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-4121"
},
{
"type": "WEB",
"url": "https://github.com/jylsec/vuldb/blob/main/Netgear/netgear_JWNR2000v2/Command_injection-cmd_wireless-port_phy_set/README.md"
},
{
"type": "WEB",
"url": "https://vuldb.com/?ctiid.306601"
},
{
"type": "WEB",
"url": "https://vuldb.com/?id.306601"
},
{
"type": "WEB",
"url": "https://vuldb.com/?submit.560775"
},
{
"type": "WEB",
"url": "https://www.netgear.com"
}
],
"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-77JC-Q8HG-FHFV
Vulnerability from github – Published: 2022-02-25 00:01 – Updated: 2023-08-08 15:31TOTOLink T6 V5.9c.4085_B20190428 was discovered to contain a command injection vulnerability in the "Main" function. This vulnerability allows attackers to execute arbitrary commands via the QUERY_STRING parameter.
{
"affected": [],
"aliases": [
"CVE-2022-25084"
],
"database_specific": {
"cwe_ids": [
"CWE-77"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2022-02-24T15:15:00Z",
"severity": "CRITICAL"
},
"details": "TOTOLink T6 V5.9c.4085_B20190428 was discovered to contain a command injection vulnerability in the \"Main\" function. This vulnerability allows attackers to execute arbitrary commands via the QUERY_STRING parameter.",
"id": "GHSA-77jc-q8hg-fhfv",
"modified": "2023-08-08T15:31:44Z",
"published": "2022-02-25T00:01:03Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2022-25084"
},
{
"type": "WEB",
"url": "https://github.com/EPhaha/IOT_vuln/blob/main/TOTOLink/T6/README.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-77JF-5MCG-G6M9
Vulnerability from github – Published: 2022-05-24 17:47 – Updated: 2025-10-22 00:32A command injection vulnerability has been reported to affect QTS and QuTS hero. If exploited, this vulnerability allows attackers to execute arbitrary commands in a compromised application. We have already fixed this vulnerability in the following versions: QTS 4.5.2.1566 Build 20210202 and later QTS 4.5.1.1495 Build 20201123 and later QTS 4.3.6.1620 Build 20210322 and later QTS 4.3.4.1632 Build 20210324 and later QTS 4.3.3.1624 Build 20210416 and later QTS 4.2.6 Build 20210327 and later QuTS hero h4.5.1.1491 build 20201119 and later
{
"affected": [],
"aliases": [
"CVE-2020-2509"
],
"database_specific": {
"cwe_ids": [
"CWE-77"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2021-04-17T04:15:00Z",
"severity": "CRITICAL"
},
"details": "A command injection vulnerability has been reported to affect QTS and QuTS hero. If exploited, this vulnerability allows attackers to execute arbitrary commands in a compromised application. We have already fixed this vulnerability in the following versions: QTS 4.5.2.1566 Build 20210202 and later QTS 4.5.1.1495 Build 20201123 and later QTS 4.3.6.1620 Build 20210322 and later QTS 4.3.4.1632 Build 20210324 and later QTS 4.3.3.1624 Build 20210416 and later QTS 4.2.6 Build 20210327 and later QuTS hero h4.5.1.1491 build 20201119 and later",
"id": "GHSA-77jf-5mcg-g6m9",
"modified": "2025-10-22T00:32:06Z",
"published": "2022-05-24T17:47:45Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2020-2509"
},
{
"type": "WEB",
"url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-2509"
},
{
"type": "WEB",
"url": "https://www.qnap.com/en/security-advisory/qsa-21-05"
}
],
"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-77MP-2CW4-V2WM
Vulnerability from github – Published: 2025-03-06 18:31 – Updated: 2025-03-06 18:31SeaCMS v13.3 was discovered to contain a remote code execution (RCE) vulnerability via the component admin_ping.php.
{
"affected": [],
"aliases": [
"CVE-2025-25794"
],
"database_specific": {
"cwe_ids": [
"CWE-77"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-02-26T15:15:27Z",
"severity": "MODERATE"
},
"details": "SeaCMS v13.3 was discovered to contain a remote code execution (RCE) vulnerability via the component admin_ping.php.",
"id": "GHSA-77mp-2cw4-v2wm",
"modified": "2025-03-06T18:31:01Z",
"published": "2025-03-06T18:31:01Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-25794"
},
{
"type": "WEB",
"url": "https://github.com/Ka7arotto/Seacms/blob/main/Seacms13.3-rce-4.md"
},
{
"type": "WEB",
"url": "https://www.seacms.com"
},
{
"type": "WEB",
"url": "http://seacms.com"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:L/I:H/A:N",
"type": "CVSS_V3"
}
]
}
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.