Is CVE-2026-102276 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-102276 being exploited in the wild.

How severe is CVE-2026-102276?

High severity, with a CVSS score of 7.5, published 28 September 2026.

Which products and versions are affected?

Juliangruber Brace-Expansion before 1.1.19, 2.1.5, 3.0.7, and 5.0.10; brace-expansion (npm) SEMVER:introduced=4.0.0,fixed=5.0.10.

Is there a fix for CVE-2026-102276?

Yes. brace-expansion (npm): upgrade to 5.0.10 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-102276 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-102276?

Check whether you run Juliangruber Brace-Expansion or brace-expansion (npm) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-102276: brace-expansion stack exhaustion denial of service

CVE-2026-102276 · Severity: high · CVSS 7.5 · Published 2026-09-28

The brace-expansion library parses brace-pattern strings into expanded output, commonly used in command-line tools and build systems. A remote attacker can craft malicious input patterns that exhaust the native stack during parsing, crashing the Node.js process and causing a denial of service. No data exposure or privilege escalation occurs; the impact is process termination and service outage.

Technologies: Juliangruber Brace-Expansion, brace-expansion (npm). Vendors: Juliangruber, npm.

Quick answers

Is CVE-2026-102276 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-102276 being exploited in the wild.
How severe is CVE-2026-102276?: High severity, with a CVSS score of 7.5, published 28 September 2026.
Which products and versions are affected?: Juliangruber Brace-Expansion before 1.1.19, 2.1.5, 3.0.7, and 5.0.10; brace-expansion (npm) SEMVER:introduced=4.0.0,fixed=5.0.10.
Is there a fix for CVE-2026-102276?: Yes. brace-expansion (npm): upgrade to 5.0.10 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-102276 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-102276?: Check whether you run Juliangruber Brace-Expansion or brace-expansion (npm) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

brace-expansion (npm): upgrade to 5.0.10 or later
```
npm install brace-expansion@5.0.10
```

Technical details

The vulnerability is a stack exhaustion flaw in the parseCommaParts function, which processes brace patterns recursively. Two attack paths exist: (1) deeply nested brace groups cause recursive stack exhaustion at ~7,000 groups, and (2) arrays passed to push.apply() with ~125,000 elements overflow the stack via argument expansion, both occurring during parsing before output is generated. The fix converts parseCommaParts to iterative logic and replaces push.apply with element-by-element appending.

Affected products

juliangruber brace-expansion before 1.1.19, 2.1.5, 3.0.7, and 5.0.10

Identifiers

CVE-2026-102276
GHSA-6j4f-fj2g-mc7p

Timeline

2026-09-28: disclosed
2026-09-14: patched: Fix commits merged to main branch

References

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