CVE-2026-5680 (GCVE-0-2026-5680)
Vulnerability from cvelistv5 – Published: 2026-08-27 16:25 – Updated: 2026-08-27 16:25
VLAI
EPSS
VEX
Title
Undertow-core: undertow: denial of service via websocket permessage-deflate processing
Summary
A flaw was found in Undertow. A remote attacker could exploit this vulnerability by sending specially crafted WebSocket messages with permessage-deflate negotiated. This could lead to excessive memory consumption due to the PerMessageDeflateFunction.largerBuffer() method using exponential doubling, resulting in a Denial of Service (DoS) for the affected application.
Severity
7.5 (High)
CWE
- CWE-770 - Allocation of Resources Without Limits or Throttling
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://access.redhat.com/security/cve/CVE-2026-5680 | vdb-entryx_refsource_REDHAT |
| https://bugzilla.redhat.com/show_bug.cgi?id=2455350 | issue-trackingx_refsource_REDHAT |
Impacted products
12 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Red Hat | Red Hat build of Apache Camel for Spring Boot 4 |
cpe:/a:redhat:camel_spring_boot:4
|
||
| Red Hat | Red Hat build of Apache Camel - HawtIO 4 |
cpe:/a:redhat:apache_camel_hawtio:4
|
||
| Red Hat | Red Hat Data Grid 8 |
cpe:/a:redhat:jboss_data_grid:8
|
||
| Red Hat | Red Hat Enterprise Linux 10 |
cpe:/o:redhat:enterprise_linux:10
|
||
| Red Hat | Red Hat Enterprise Linux 8 |
cpe:/o:redhat:enterprise_linux:8
|
||
| Red Hat | Red Hat Enterprise Linux 9 |
cpe:/o:redhat:enterprise_linux:9
|
||
| Red Hat | Red Hat Fuse 7 |
cpe:/a:redhat:jboss_fuse:7
|
||
| Red Hat | Red Hat JBoss Enterprise Application Platform 7 |
cpe:/a:redhat:jboss_enterprise_application_platform:7
|
||
| Red Hat | Red Hat JBoss Enterprise Application Platform 8 |
cpe:/a:redhat:jboss_enterprise_application_platform:8
|
||
| Red Hat | Red Hat JBoss Enterprise Application Platform Expansion Pack |
cpe:/a:redhat:jbosseapxp
|
||
| Red Hat | Red Hat Process Automation 7 |
cpe:/a:redhat:jboss_enterprise_bpms_platform:7
|
||
| Red Hat | Red Hat Single Sign-On 7 |
cpe:/a:redhat:red_hat_single_sign_on:7
|
Date Public
2026-07-04 23:59
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"redhat_vex": {
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"current_release_date": "2026-08-27T17:11:09+00:00",
"cve": "CVE-2026-5680",
"id": "CVE-2026-5680",
"initial_release_date": "2026-07-04T23:59:59+00:00",
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"title": "undertow-core: Undertow: Denial of Service via WebSocket permessage-deflate processing",
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}
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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