CVE-2026-91920 (GCVE-0-2026-91920)
Vulnerability from cvelistv5 – Published: 2026-10-30 01:16 – Updated: 2026-10-30 01:16
VLAI
EPSS
VEX
Title
Undertow: undertow: chunkreader message length permits chunk-size overflow
Summary
A flaw was found in the ChunkReader component of the Undertow web server, which is used to handle chunked transfer encoding in HTTP requests. The issue occurs because a security check for the chunk size is performed before the value is shifted, allowing a specifically crafted 15-digit chunk size to bypass the limit and overflow into internal state flags. This can cause the server to terminate a request body prematurely and interpret the remaining data as a separate, smuggled request.
Severity
6.5 (Medium)
CWE
- CWE-444 - Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://access.redhat.com/security/cve/CVE-2026-91920 | vdb-entryx_refsource_REDHAT |
| https://bugzilla.redhat.com/show_bug.cgi?id=2528758 | issue-trackingx_refsource_REDHAT |
Impacted products
8 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 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 Single Sign-On 7 |
cpe:/a:redhat:red_hat_single_sign_on:7
|
Date Public
2026-10-29 12:11
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