Common Weakness Enumeration

CWE-183

Allowed

Permissive List of Allowed Inputs

Abstraction: Base · Status: Draft

The product implements a protection mechanism that relies on a list of inputs (or properties of inputs) that are explicitly allowed by policy because the inputs are assumed to be safe, but the list is too permissive - that is, it allows an input that is unsafe, leading to resultant weaknesses.

93 vulnerabilities reference this CWE, most recent first.

GHSA-4R96-7XRX-4GCR

Vulnerability from github – Published: 2026-07-24 15:33 – Updated: 2026-07-24 15:33
VLAI
Details

Jan through 0.8.4, fixed in commit 3e1c1e7, contains a CORS misconfiguration vulnerability in its local API server that allows network-adjacent attackers to bypass trusted host restrictions by exploiting the server's replacement of user-configured trusted hosts with a wildcard that reflects arbitrary origins with credentials. Attackers on the local network or using DNS rebinding can reach the unauthenticated OpenAI-compatible API to perform inference, enumerate models, invoke MCP tools, and read cross-origin responses.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2026-66005"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-183"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-07-24T15:19:07Z",
    "severity": "MODERATE"
  },
  "details": "Jan through 0.8.4, fixed in commit 3e1c1e7, contains a CORS misconfiguration vulnerability in its local API server that allows network-adjacent attackers to bypass trusted host restrictions by exploiting the server\u0027s replacement of user-configured trusted hosts with a wildcard that reflects arbitrary origins with credentials. Attackers on the local network or using DNS rebinding can reach the unauthenticated OpenAI-compatible API to perform inference, enumerate models, invoke MCP tools, and read cross-origin responses.",
  "id": "GHSA-4r96-7xrx-4gcr",
  "modified": "2026-07-24T15:33:03Z",
  "published": "2026-07-24T15:33:03Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-66005"
    },
    {
      "type": "WEB",
      "url": "https://github.com/janhq/jan/issues/8453"
    },
    {
      "type": "WEB",
      "url": "https://github.com/janhq/jan/pull/8506"
    },
    {
      "type": "WEB",
      "url": "https://github.com/janhq/jan/commit/3e1c1e724f696620d89bb4a9cc18a380e0753757"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/jan-local-api-server-cors-origin-reflection-via-binding"
    }
  ],
  "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: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-58PR-GW4M-RW8V

Vulnerability from github – Published: 2026-05-06 21:31 – Updated: 2026-05-06 21:31
VLAI
Details

OpenClaw before 2026.4.15 contains an arbitrary file read vulnerability in the QMD backend memory_get function that allows callers to read any Markdown files within the workspace root. Attackers with access to the memory tool can bypass path restrictions by providing arbitrary workspace Markdown paths to read files outside canonical memory locations or indexed QMD result sets.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2026-44111"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-183"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-05-06T20:16:34Z",
    "severity": "LOW"
  },
  "details": "OpenClaw before 2026.4.15 contains an arbitrary file read vulnerability in the QMD backend memory_get function that allows callers to read any Markdown files within the workspace root. Attackers with access to the memory tool can bypass path restrictions by providing arbitrary workspace Markdown paths to read files outside canonical memory locations or indexed QMD result sets.",
  "id": "GHSA-58pr-gw4m-rw8v",
  "modified": "2026-05-06T21:31:42Z",
  "published": "2026-05-06T21:31:42Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/openclaw/openclaw/security/advisories/GHSA-f934-5rqf-xx47"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-44111"
    },
    {
      "type": "WEB",
      "url": "https://github.com/openclaw/openclaw/commit/37d5971db36491d5050efd42c333cbe0b98ed292"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/openclaw-arbitrary-markdown-file-read-via-qmd-memory-get"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:N/VA:N/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-6676-9PQR-4CW3

Vulnerability from github – Published: 2023-10-17 09:30 – Updated: 2025-02-13 18:31
VLAI
Details

Grafana is an open-source platform for monitoring and observability.

In Grafana Enterprise, Request security is a deny list that allows admins to configure Grafana in a way so that the instance doesn’t call specific hosts.

However, the restriction can be bypassed used punycode encoding of the characters in the request address.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2023-4399"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-183"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2023-10-17T08:15:09Z",
    "severity": "HIGH"
  },
  "details": "Grafana is an open-source platform for monitoring and observability. \n\nIn Grafana Enterprise, Request security is a deny list that allows admins to configure Grafana in a way so that the instance doesn\u2019t call specific hosts.\n\nHowever, the restriction can be bypassed used punycode encoding of the characters in the request address.",
  "id": "GHSA-6676-9pqr-4cw3",
  "modified": "2025-02-13T18:31:57Z",
  "published": "2023-10-17T09:30:23Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-4399"
    },
    {
      "type": "WEB",
      "url": "https://grafana.com/security/security-advisories/cve-2023-4399"
    },
    {
      "type": "WEB",
      "url": "https://security.netapp.com/advisory/ntap-20231208-0003"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:N/A:L",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-68XJ-H57P-GG5J

Vulnerability from github – Published: 2026-02-10 21:31 – Updated: 2026-02-10 21:31
VLAI
Details

Under specific conditions when processing a maliciously crafted value of type Hash r, Mongoid::Criteria.from_hash may allow for executing arbitrary Ruby code.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2026-2302"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-183"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-02-10T19:16:04Z",
    "severity": "MODERATE"
  },
  "details": "Under specific conditions when processing a maliciously crafted value of type Hash r, Mongoid::Criteria.from_hash may allow for executing arbitrary Ruby code.",
  "id": "GHSA-68xj-h57p-gg5j",
  "modified": "2026-02-10T21:31:30Z",
  "published": "2026-02-10T21:31:30Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-2302"
    },
    {
      "type": "WEB",
      "url": "https://jira.mongodb.org/browse/MONGOID-5919"
    }
  ],
  "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:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:H/VA:N/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-6HQM-HM2V-3P2P

Vulnerability from github – Published: 2026-08-01 15:30 – Updated: 2026-08-01 15:30
VLAI
Details

axios versions 1.15.0 before 1.18.0 fail to recognize 0.0.0.0 as a loopback address in shouldBypassProxy.js, allowing requests to 0.0.0.0 to bypass NO_PROXY rules. Attackers can supply 0.0.0.0 URLs to route requests through configured proxies, potentially exposing local services when the proxy can reach the destination.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2026-67315"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-183"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-01T13:17:01Z",
    "severity": "MODERATE"
  },
  "details": "axios versions 1.15.0 before 1.18.0 fail to recognize 0.0.0.0 as a loopback address in shouldBypassProxy.js, allowing requests to 0.0.0.0 to bypass NO_PROXY rules. Attackers can supply 0.0.0.0 URLs to route requests through configured proxies, potentially exposing local services when the proxy can reach the destination.",
  "id": "GHSA-6hqm-hm2v-3p2p",
  "modified": "2026-08-01T15:30:27Z",
  "published": "2026-08-01T15:30:27Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/axios/axios/security/advisories/GHSA-f4gw-2p7v-4548"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-67315"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/axios-before-no-proxy-bypass-via"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:H/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-72J4-94RX-CR6W

Vulnerability from github – Published: 2022-02-09 00:57 – Updated: 2021-04-01 21:11
VLAI
Summary
Incorrect Permission Assignment for Critical Resource and Permissive List of Allowed Inputs in Keycloak
Details

A flaw was found in all versions of Keycloak before 10.0.0, where the NodeJS adapter did not support the verify-token-audience. This flaw results in some users having access to sensitive information outside of their permissions.

Show details on source website

{
  "affected": [
    {
      "package": {
        "ecosystem": "Maven",
        "name": "org.keycloak:keycloak-parent"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "10.0.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2020-1694"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-183",
      "CWE-732"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2021-04-01T21:11:24Z",
    "nvd_published_at": "2020-09-16T19:15:00Z",
    "severity": "MODERATE"
  },
  "details": "A flaw was found in all versions of Keycloak before 10.0.0, where the NodeJS adapter did not support the verify-token-audience. This flaw results in some users having access to sensitive information outside of their permissions.",
  "id": "GHSA-72j4-94rx-cr6w",
  "modified": "2021-04-01T21:11:24Z",
  "published": "2022-02-09T00:57:02Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2020-1694"
    },
    {
      "type": "WEB",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=1790759"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Incorrect Permission Assignment for Critical Resource and Permissive List of Allowed Inputs in Keycloak"
}

GHSA-7957-WQGW-M3J9

Vulnerability from github – Published: 2026-07-30 15:31 – Updated: 2026-07-30 15:31
VLAI
Details

MaxKey through 4.1.12, fixed in commit ddbb72f, contains an insufficient redirect URI validation vulnerability in DefaultRedirectResolver.hostMatches() that allows remote attackers to hijack OAuth 2.0 authorization codes by supplying a crafted redirect_uri whose hostname suffix matches a registered URI without proper dot-boundary anchoring. Attackers who control a domain ending with the registered redirect URI hostname can social-engineer victims into clicking a crafted authorization URL, causing the authorization code to be issued to the attacker-controlled URI and exchanged for an access token granting access to the victim's identity.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2026-67345"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-183"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-07-30T15:16:35Z",
    "severity": "HIGH"
  },
  "details": "MaxKey through 4.1.12, fixed in commit ddbb72f, contains an insufficient redirect URI validation vulnerability in DefaultRedirectResolver.hostMatches() that allows remote attackers to hijack OAuth 2.0 authorization codes by supplying a crafted redirect_uri whose hostname suffix matches a registered URI without proper dot-boundary anchoring. Attackers who control a domain ending with the registered redirect URI hostname can social-engineer victims into clicking a crafted authorization URL, causing the authorization code to be issued to the attacker-controlled URI and exchanged for an access token granting access to the victim\u0027s identity.",
  "id": "GHSA-7957-wqgw-m3j9",
  "modified": "2026-07-30T15:31:52Z",
  "published": "2026-07-30T15:31:52Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-67345"
    },
    {
      "type": "WEB",
      "url": "https://github.com/dromara/MaxKey/issues/269"
    },
    {
      "type": "WEB",
      "url": "https://github.com/dromara/MaxKey/commit/ddbb72fb24ab8e66aa422fb14b1177330bcffb45"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/maxkey-defaultredirectresolver-oauth-authorization-code-theft"
    }
  ],
  "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:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:N/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-7FX5-RX8M-8V2F

Vulnerability from github – Published: 2025-04-30 12:31 – Updated: 2025-04-30 12:31
VLAI
Details

A vulnerability in the “Network Interfaces” functionality of the web application of ctrlX OS allows a remote authenticated (lowprivileged) attacker to delete the configuration of physical network interfaces via a crafted HTTP request.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2025-24349"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-183"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2025-04-30T12:15:21Z",
    "severity": "HIGH"
  },
  "details": "A vulnerability in the \u201cNetwork Interfaces\u201d functionality of the web application of ctrlX OS allows a remote authenticated (lowprivileged) attacker to delete the configuration of physical network interfaces via a crafted HTTP request.",
  "id": "GHSA-7fx5-rx8m-8v2f",
  "modified": "2025-04-30T12:31:25Z",
  "published": "2025-04-30T12:31:25Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-24349"
    },
    {
      "type": "WEB",
      "url": "https://psirt.bosch.com/security-advisories/BOSCH-SA-640452.html"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-7MM5-2CMW-JQQ7

Vulnerability from github – Published: 2025-07-18 18:30 – Updated: 2025-07-18 18:30
VLAI
Details

Permissive list of allowed inputs in Microsoft Purview allows an authorized attacker to elevate privileges over a network.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2025-53762"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-183"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2025-07-18T17:15:44Z",
    "severity": "HIGH"
  },
  "details": "Permissive list of allowed inputs in Microsoft Purview allows an authorized attacker to elevate privileges over a network.",
  "id": "GHSA-7mm5-2cmw-jqq7",
  "modified": "2025-07-18T18:30:29Z",
  "published": "2025-07-18T18:30:29Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-53762"
    },
    {
      "type": "WEB",
      "url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-53762"
    }
  ],
  "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:N",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-82FG-2R99-H7V6

Vulnerability from github – Published: 2026-06-17 18:35 – Updated: 2026-06-18 14:45
VLAI
Summary
Duplicate Advisory: PickleScan's pkgutil.resolve_name has a universal blocklist bypass
Details

Duplicate Advisory

This advisory has been withdrawn because it is a duplicate of GHSA-vvpj-8cmc-gx39. This link is maintained to preserve external references.

Original Description

picklescan before 1.0.4 fails to block pkgutil.resolve_name, allowing attackers to bypass the entire blocklist by resolving any dangerous function through indirect REDUCE calls. Remote attackers can invoke any blocked function such as os.system, builtins.exec, or subprocess.call to achieve remote code execution.

Show details on source website

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "picklescan"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.0.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [],
  "database_specific": {
    "cwe_ids": [
      "CWE-183"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-06-18T14:45:20Z",
    "nvd_published_at": "2026-06-17T17:16:50Z",
    "severity": "CRITICAL"
  },
  "details": "### Duplicate Advisory\nThis advisory has been withdrawn because it is a duplicate of GHSA-vvpj-8cmc-gx39. This link is maintained to preserve external references.\n\n### Original Description\npicklescan before 1.0.4 fails to block pkgutil.resolve_name, allowing attackers to bypass the entire blocklist by resolving any dangerous function through indirect REDUCE calls. Remote attackers can invoke any blocked function such as os.system, builtins.exec, or subprocess.call to achieve remote code execution.",
  "id": "GHSA-82fg-2r99-h7v6",
  "modified": "2026-06-18T14:45:20Z",
  "published": "2026-06-17T18:35:57Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/mmaitre314/picklescan/security/advisories/GHSA-vvpj-8cmc-gx39"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-3490"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/picklescan-universal-blocklist-bypass-via-pkgutil-resolve-name"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/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:H/SI:H/SA:H/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"
    }
  ],
  "summary": "Duplicate Advisory: PickleScan\u0027s pkgutil.resolve_name has a universal blocklist bypass",
  "withdrawn": "2026-06-18T14:45:20Z"
}

No mitigation information available for this CWE.

CAPEC-120: Double Encoding

The adversary utilizes a repeating of the encoding process for a set of characters (that is, character encoding a character encoding of a character) to obfuscate the payload of a particular request. This may allow the adversary to bypass filters that attempt to detect illegal characters or strings, such as those that might be used in traversal or injection attacks. Filters may be able to catch illegal encoded strings, but may not catch doubly encoded strings. For example, a dot (.), often used in path traversal attacks and therefore often blocked by filters, could be URL encoded as %2E. However, many filters recognize this encoding and would still block the request. In a double encoding, the % in the above URL encoding would be encoded again as %25, resulting in %252E which some filters might not catch, but which could still be interpreted as a dot (.) by interpreters on the target.

CAPEC-3: Using Leading 'Ghost' Character Sequences to Bypass Input Filters

Some APIs will strip certain leading characters from a string of parameters. An adversary can intentionally introduce leading "ghost" characters (extra characters that don't affect the validity of the request at the API layer) that enable the input to pass the filters and therefore process the adversary's input. This occurs when the targeted API will accept input data in several syntactic forms and interpret it in the equivalent semantic way, while the filter does not take into account the full spectrum of the syntactic forms acceptable to the targeted API.

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-71: Using Unicode Encoding to Bypass Validation Logic

An attacker may provide a Unicode string to a system component that is not Unicode aware and use that to circumvent the filter or cause the classifying mechanism to fail to properly understanding the request. That may allow the attacker to slip malicious data past the content filter and/or possibly cause the application to route the request incorrectly.