CVE-2026-19879Io.undertow/undertow: undertow: http response header integrity issue due to character truncation
Updated under an hour ago ()
Does this affect you?
It affects Red Hat build of Apache Camel for Spring Boot 4 and 4 other products. Add what you run to find out whether that includes you.
No exploitation reported and no EPSS estimate yet.
Do this next
Free account, 1 product
A flaw was found in Undertow, an HTTP server, within its HTTP response header writing path. The `writeString()` method performs a silent narrowing cast from 16-bit Unicode characters to 8-bit bytes when writing HTTP response header values. A remote attacker can exploit this by supplying specific Unicode characters in user-controlled input that an application places into response headers. This can lead to the truncation of these characters into ASCII control characters or special symbols, potentially resulting in limited integrity impact or information disclosure if the application does not properly sanitize user input.
- CVSS
- 5.3 MEDIUM (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
- Weakness (CWE)
- CWE-681
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- Not loaded for this CVE
- Assigned by
- redhat
- NVD analysis
- Awaiting Analysis
- Record last updated
- Aug 14, 2026
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
Red Hat Red Hat build of Apache Camel for Spring Boot 4 redhat:camel_spring_boot | 4 | CNA record |
Red Hat Red Hat Enterprise Linux 10 redhat:enterprise_linux | 10 | CNA record |
Red Hat Red Hat JBoss Enterprise Application Platform 7 redhat:jboss_enterprise_application_platform | 7 | CNA record |
Red Hat Red Hat JBoss Enterprise Application Platform Expansion Pack redhat:jbosseapxp | All versions | CNA record |
Red Hat Red Hat Single Sign-On 7 redhat:red_hat_single_sign_on | 7 | CNA record |
References
- https://access.redhat.com/security/cve/CVE-2026-19879vdb-entry, x-refsource-redhat
- https://bugzilla.redhat.com/show_bug.cgi?id=2516038issue-tracking, x-refsource-redhat
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.