Resource exhaustion in Org.webjars.npm:pacote

CVE-2026-9496

Versions of the package pacote from 11.2.7 and before 21.5.1 are vulnerable to Denial of Service (DoS) via the addGitSha function. An attacker can exploit this vulnerability by supplying a specially crafted spec.rawSpec value that triggers the function’s regex replacement and string-manipulation logic, causing excessive CPU consumption and potentially stalling or crashing the process.

Vulnerability class: ReDoS (Regular Expression Denial of Service)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.006 (48.1th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 48th percentile — 48.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-9496: held from 0.003 to 0.006.

EPSS over last 30 days · oldest: 0.003 · newest: 0.006 · change: +0.003

Affected products

  • Org.webjars.npm:pacote — versions 11.2.7
  • Pacote — versions 11.2.7

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-9496?
CVE-2026-9496 is a high-severity vulnerability in Org.webjars.npm:pacote, classified under Inefficient Regular Expression Complexity. CVSS score: 7.5/10. Published 2026-05-26.
How severe is CVE-2026-9496?
High severity. CVSS v3 base score is 7.5 out of 10.