TI-2026-50878 Aliases CVE-2026-72639 GHSA-m2jm-f3w6-vg8c

Memory Allocation with Excessive Size Value in Elasticsearch Highlighting Leading to Denial of Service

LOW 29CWE-789Published 2026-08-13 · Updated 2026-08-13

Key facts

Attack vector: Network
Privileges required: Low
User interaction: None
Attack complexity: Low
Impact type: Denial of service
Confidentiality · integrity · availability: None · None · High
Fix status: No fix listed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-789.

Summary

Elasticsearch does not enforce an upper bound on a user-supplied count accepted by a search highlighting option, and the allocation derived from that count is not accounted against any circuit breaker. An authenticated user holding only read privileges on a single searchable index can submit one small search request that causes the node to reserve an excessively large internal data structure. The allocation occurs before the existing highlighting safety limits are evaluated, so memory exhaustion raises a fatal error that terminates the Elasticsearch node process. This results in a denial of service for the affected node and degrades cluster routing and health. The defect is not volumetric and does not depend on the size of the indexed data, so a single request is sufficient.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.0042 36th percentileScored 2026-11-07

Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: No
Technical impact: Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
Elastic	Elasticsearch	8.19.0 – 8.19.19; 9.3.0 – 9.5.0	—	No fix listed	CNA

Elasticsearch VendorElastic Affected 8.19.0 – 8.19.19; 9.3.0 – 9.5.0 Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPE	Versions	Role	Vendor
cpe:2.3:a:elastic:elasticsearch::::::::	8.19.0 to before 8.19.20; 9.3.0 to before 9.4.5; 9.5.0 to before 9.5.1	Vulnerable	Elastic

cpe:2.3:a:elastic:elasticsearch:*:*:*:*:*:*:*:* Versions 8.19.0 to before 8.19.20; 9.3.0 to before 9.4.5; 9.5.0 to before 9.5.1 Vulnerable ·Elastic

Remediation

No fixed version listed by the sources yet.

Timeline

2026-10-02 Threatist record created from CVE-2026-72639
2026-10-03 Alias added: GHSA-m2jm-f3w6-vg8c

References

Advisory 1

https://discuss.elastic.co/t/elasticsearch-8-19-20-9-4-5-9-5-1-security-update-esa-2026-120/389503

TI-2015-01295 The Groovy scripting engine in Elasticsearch before 1.3.8 and 1.4.x before 1.4.3 allows… KEVCVSS 3.1CRITICAL 9.8
TI-2014-02491 The default configuration in Elasticsearch before 1.2 enables dynamic scripting, which… KEVCVSS 3.1HIGH 8.1
TI-2023-15037 Elasticsearch StackOverflow vulnerability CVSS 3.1HIGH 7.5
TI-2021-05135 Information disclosure in Elasticsearch CVSS 3.1MEDIUM 6.5
TI-2021-05136 All versions of Elastic Cloud Enterprise has the Elasticsearch “anonymous” user enabled… CVSS 3.1HIGH 7.5
TI-2015-04530 Elasticsearch before 1.6.1 allows remote attackers to execute arbitrary code via… CVSS 3.0CRITICAL 9.8

See all 90 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences