Is CVE-2026-102278 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-102278 being exploited in the wild.

How severe is CVE-2026-102278?

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

Which products and versions are affected?

Juliangruber Brace-Expansion before 1.1.20, 2.1.6, 3.0.8, and 5.0.11; brace-expansion (npm) SEMVER:introduced=4.0.0,fixed=5.0.11.

Is there a fix for CVE-2026-102278?

Yes. brace-expansion (npm): upgrade to 5.0.11 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-102278 attacked?

It is attacked over the network.

Am I affected by CVE-2026-102278?

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-2026-102278: brace-expansion stack exhaustion in deeply nested brace groups

CVE-2026-102278 · Severity: high · CVSS 7.5 · Published 2026-09-28

The brace-expansion library is a Node.js utility that parses and expands shell-style brace patterns (like {a,b,c}). An attacker who can supply deeply nested brace patterns to the expand function can trigger uncontrolled recursion that exhausts the process stack, causing the Node.js application to crash—a denial-of-service attack that requires only about 6KB of malicious input.

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

Quick answers

Is CVE-2026-102278 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-102278 being exploited in the wild.
How severe is CVE-2026-102278?: High severity, with a CVSS score of 7.5, published 28 September 2026.
Which products and versions are affected?: Juliangruber Brace-Expansion before 1.1.20, 2.1.6, 3.0.8, and 5.0.11; brace-expansion (npm) SEMVER:introduced=4.0.0,fixed=5.0.11.
Is there a fix for CVE-2026-102278?: Yes. brace-expansion (npm): upgrade to 5.0.11 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-102278 attacked?: It is attacked over the network.
Am I affected by CVE-2026-102278?: 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 5.0.11 or later
```
npm install brace-expansion@5.0.11
```

Technical details

The expand_() function recursively processes brace groups during comma-member expansion and single-set re-wrapping, with one recursion per nesting level. Deeply nested patterns like '{'.repeat(3200) + 'a,b' + '}'.repeat(3200) cause stack exhaustion before existing max or maxLength output limits trigger. The fix introduces a maxDepth bound (default 1000) to limit recursion depth and treat over-nested groups as literal text.

Affected products

juliangruber brace-expansion before 1.1.20, 2.1.6, 3.0.8, and 5.0.11

Identifiers

CVE-2026-102278
GHSA-qhr7-859c-m2p7

Timeline

2026-09-28: disclosed
2026-09-14: patched

References

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