CVE-2026-2391: qs's arrayLimit bypass in comma parsing allows denial of service

February 12, 2026

The arrayLimit option in qs does not enforce limits for comma-separated values when comma: true is enabled, allowing attackers to cause denial-of-service via memory exhaustion. This is a bypass of the array limit enforcement, similar to the bracket notation bypass addressed in GHSA-6rw7-vpxm-498p (CVE-2025-15284).

References

github.com/advisories/GHSA-w7fw-mjwx-w883
github.com/ljharb/qs
github.com/ljharb/qs/commit/f6a7abff1f13d644db9b05fe4f2c98ada6bf8482
github.com/ljharb/qs/security/advisories/GHSA-w7fw-mjwx-w883
nvd.nist.gov/vuln/detail/CVE-2026-2391

Code Behaviors & Features

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