Inefficient Regular Expression Complexity in Elasticsearch Leading to Denial of Service (Elastic Elasticsearch)
At a glance
- Source
- NVD
- EPSS
- EPSS 0.35 % · percentile 28 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- elastic
- NVD status
- Analyzed
Description
Inefficient Regular Expression Complexity (CWE-1333) in Elasticsearch can lead to denial of service via Regular Expression Exponential Blowup (CAPEC-492). The ES|QL CHUNK function's recursive chunking strategy accepts a list of user-supplied regular expressions used as text-splitting separators, without validating their computational complexity or bounding their execution time. An authenticated user with read access to any text-based index can submit a specially crafted regular expression that triggers catastrophic backtracking, consuming excessive CPU on Elasticsearch worker threads and degrading query throughput for other tenants on the affected node. The cluster does not crash as a result of this issue.
Weaknesses (CWE)
- CWE-1333 — Inefficient Regular Expression Complexity
References
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | MEDIUM 4.3 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L | elastic |
| CVSS 3.1 | MEDIUM 4.3 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L | NVD · security@elastic.co (Secondary) |
European references
- ENISA EUVD · EUVD-2026-93929
- GCVE · GCVE-0-2026-102408
CERT-FR advisories
- CERTFR-2026-AVI-1276 — Multiples vulnérabilités dans les produits Elastic · cert.ssi.gouv.fr
Affected configurations (NVD CPE)
cpe:2.3:a:elastic:elasticsearch:*:*:*:*:*:*:*:*≥ 8.19.0 < 8.19.22cpe:2.3:a:elastic:elasticsearch:*:*:*:*:*:*:*:*≥ 9.1.0 < 9.4.8cpe:2.3:a:elastic:elasticsearch:*:*:*:*:*:*:*:*≥ 9.5.0 < 9.5.5
Affected products
| Product | Versions |
|---|---|
| Elastic · Elasticsearch | affected 8.19.0 ≤ 8.19.21 ; affected 9.1.0 ≤ 9.3.8 ; affected 9.4.0 ≤ 9.4.7 ; affected 9.5.0 ≤ 9.5.4 |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| CERT-FR (ANSSI) | Licence Ouverte / Etalab 2.0 |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |