Widespread use of a popular Node.js library; high-severity DoS could disrupt services across many apps.
CVE-2026-25547
DoS via unbounded brace expansion in @isaacs/brace-expansion <5.0.1
Is CVE-2026-25547 being exploited?
Not confirmed. CVE-2026-25547 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.50% probability of exploitation in the next 30 days.
How severe is CVE-2026-25547?
CVE-2026-25547 is rated Critical with a CVSS score of 9.2. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-25547?
Yes. A fix has been recorded for CVE-2026-25547. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-25547 affect?
CVE-2026-25547 affects @isaacs/brace-expansion <5.0.1, Node.js apps depending on the library, JS tooling using brace-expansion. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-25547?
Upgrade to 5.0.1+
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Exploitable DoS: crafted brace patterns cause CPU/memory exhaustion and crash Node.js processes.
Patch when possible
- affected< 5.0.1
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.