CVE-2026-14257: brace-expansion DoS via unbounded expansion length causing an out-of-memory process crash
CSIRTS triage
- What
- Unbounded brace expansion allows attacker to generate excessive output causing out-of-memory process crash.
- Who is affected
- Applications using the brace-expansion npm package to process untrusted input.
- Urgency
- High severity (CVSS 7.5); remote denial of service via specially crafted brace expansion patterns.
- Action
- Update brace-expansion package to patched version with expansion length limits.
AI-assisted analysis generated from the source advisory — verify against the original.
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Details
Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-14257
Exploitation outlook
EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.
- Low exploitation riskCVE-2026-142570.34% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 27% of all EPSS-scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2026-14257 | coverage & exploitation status | NVD · CVE.org |
Same CVEs, other sources
How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.
- high[NEW] [high] Red Hat Enterprise Linux (nodejs:24): Multiple vulnerabilitiescert-bund
- highGHSA-mh99-v99m-4gvg: brace-expansion: DoS via unbounded expansion length causing an out-of-memory process cras…ghsa
- highCVE-2026-14257: brace-expansion through 5.0.7 is vulnerable to denial of service via memory exhaustion. The ex…nvd
Recent advisories for brace-expansion DoS via
A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.
- highCVE-2026-69152: brace-expansion: DoS via unbounded intermediate arrays, bypassing the CVE-2026-14257 mitigatio…msrc · 2026-08-11
- highGHSA-rgw5-rvv9-x895: brace-expansion: DoS via unbounded intermediate arrays, bypassing the CVE-2026-14257 miti…ghsa · 2026-08-03
- highGHSA-mh99-v99m-4gvg: brace-expansion: DoS via unbounded expansion length causing an out-of-memory process cras…ghsa · 2026-07-24
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