Patch transitive brace-expansion DoS vuln to 1.1.16 via npm override

[Copilot]

brace-expansion@1.1.11 is vulnerable to exponential-time processing in expand() (GHSA-3jxr-9vmj-r5cp / CVE-2026-13149), enabling DoS with small crafted brace patterns. This PR remediates the vulnerable resolution with the lowest patched version to minimize dependency risk.

• Dependency remediation

  • Added an npm overrides pin for brace-expansion to 1.1.16 in package.json.
  • Refreshed package-lock.json so the transitive Jest/Glob/Minimatch chain resolves to the patched version.

• Reachability assessment (confidence: high)

  • Affected API: brace-expansion.expand().
  • Repository search found no direct runtime usage of brace-expansion, minimatch, glob, or expand( in application code.
  • Current exposure is through dev/test tooling dependency paths (jest -> @jest/reporters -> glob -> minimatch -> brace-expansion), so this is primarily scanner/supply-chain risk reduction rather than an actively reachable production code path.

{
  "overrides": {
    "brace-expansion": "1.1.16"
  }
}

Original prompt

---

This section details the Dependabot vulnerability alert you should resolve

<alert_title>brace-expansion: DoS via exponential-time expansion of consecutive non-expanding {} groups</alert_title>
<alert_description>### Summary
brace-expansion's expand() exhibits exponential-time - O(2ⁿ) - behavior in the number of consecutive non-expanding {} groups. A short, all-ASCII input (~90 bytes/30 groups) blocks the calling thread for minutes; a slightly longer input hangs it effectively indefinitely. Because the dominant consumers run on Node's single-threaded event loop, one small input can fully stall a worker/process.

In expand_, post is computed unconditionally at the top of the function, before the early-return branches that don't use it:

const post = m.post.length ? expand_(m.post, max, false) : [''];   // always recurses
  ...
if (!isSequence && !isOptions) {
  if (m.post.match(/,(?!,).*\}/)) {
    str = m.pre + '{' + m.body + escClose + m.post;
    return expand_(str, max, true); // restart — `post` discarded
  }
  return [str];
}

For input like a{},{},…, the first {} is non-expanding, so control reaches the {a},b} rewrite branch - but expand_ has already recursed into post over the entire remaining tail, only to throw the result away.
Each level therefore spawns two recursive expansions over essentially the same remaining work: T(n) = 2·T(n−1) ⇒ O(2ⁿ).

The max option does not mitigate this: max only bounds the output-building loops; neither the post recursion nor the rewrite recursion consults it.

Measured on 5.0.6:

groups (n)	input bytes	time
20	60	130 ms
24	72	1.9 s
26	78	7.8 s
30 (PoC)	90	~2 min

Proof of concept

const { expand } = require('brace-expansion');
// 30 non-expanding groups, ~90 bytes — blocks for minutes:
expand('a{},{},{},{},{},{},{},{},{},{},{},{},{},{},{},{},{},{},{},{},{},{},{},{},{},{},{},{},{},{}');

Impact

Any application that passes attacker-influenced strings to brace-expansion.expand() - directly or transitively via minimatch/glob brace patterns - can be driven into a multi-minute-to-indefinite CPU hang by a tiny request, denying service on that thread/process.

Remediation

Upgrade to a patched release. The fix:

1. Defers computing post until after the early-return branches (and computes it locally in the $-suffix branch), so post is only expanded when a brace set actually expands and the value is used. This alone removes the exponential.
2. Converts the {a},b} rewrite from recursion to an in-function loop, so a long run of rewrites cannot grow the call stack.

Verified: the PoC drops from ~2 min to 0.55 ms, 5,000 groups complete in ~344 ms, and output is identical to 5.0.6 across a behavioral-equivalence suite (sequences, padding, $-prefix, a{},b}c, {},a}b, x{{a,b}}y, etc.). Post-fix complexity is ~O(n²) on this input class - acceptable for the security fix; a linear rewrite can be a non-urgent follow-up.

If immediate upgrade isn't possible, avoid passing untrusted input to expand() / glob brace patterns, or run such expansion under a timeout/worker.</alert_description>

high
GHSA-3jxr-9vmj-r5cp, CVE-2026-13149
brace-expansion
npm
<vulnerable_versions>1.1.11</vulnerable_versions>
<patched_version>1.1.16</patched_version>
<manifest_path>package-lock.json</manifest_path>

https://github.com/juliangruber/brace-expansion/security/advisories/GHSA-3jxr-9vmj-r5cp https://nvd.nist.gov/vuln/detail/CVE-2026-13149 https://github.com/juliangruber/brace-expansion/pull/122 https://github.com/juliangruber/brace-expansion/pull/123 https://github.com/juliangruber/brace-expansion/commit/835d6be91201122d9adffb0c0c8c094189ace265 https://github.com/juliangruber/brace-expansion/commit/c7e33ec13ac1a684c116720843ce24e208611754 https://github.com/juliangruber/brace-expansion/commit/d74e63030c012e3b7ae81657b8d665619cd51b95 https://github.com/juliangruber/brace-expansion/releases/tag/v1.1.16 https://github.com/juliangruber/brace-expansion/releases/tag/v2.1.2 https://github.com/juliangruber/brace-expansion/releases/tag/v5.0.7 https://www.npmjs.com/package/brace-expansion https://github.com/advisories/GHSA-3jxr-9vmj-r5cp

<task_instructions>Resolve this alert by updating the affected package to a non-vulnerable version. Prefer the lowest non-vulnerable version (see the patched_version field above) over the latest to minimize breaking changes. Include a Reachability Assessment section in the PR description. Review the alert_description field to understand which APIs, features, or configurations are affected, then search the codebase for usage of those specific items. If the vulnerable code path is reachable, explain how (which files, APIs, or call sites...

• Resolves github/copilot-survey-engine alert fix: bump @opentelemetry/propagator-jaeger to 2.9.0 (CVE-2026-59892) #59

[Copilot]

Pull request overview

Pins the vulnerable transitive dependency to the lowest patched 1.x release.

Changes:

• Added a brace-expansion@1.1.16 npm override.
• Updated the lockfile resolution and integrity metadata.

Show a summary per file

File	Description
package.json	Adds the patched-version override.
package-lock.json	Resolves brace-expansion to 1.1.16.

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• Review effort level: Medium