High
undertow — security advisory
A flaw was found in EAP's undertow http/1.1 chunked-transfer decoder. missing limits on size and count would allow an attacker to use an unauthenticated connection to drive the JVM to an OutOfMemory error, stopping all deployments on the listener, and achieving Denial of Service.
- Products
- undertow
- Affected versions
- 1.3.11-1, 1.3.16-1, 1.3.16-1ubuntu0.1~esm1, 1.3.4-1, 1.3.5-1, 1.3.7-1, 1.4.20-1, 1.4.21-1, 1.4.22-1, 1.4.23-1, 1.4.23-2build1, 1.4.23-3, 1.4.23-3ubuntu0.1~esm1, 2.0.23-1, 2.0.27-1, 2.0.28-1, 2.0.29-1, 2.0.29-1ubuntu0.1~esm1, 2.2.12-1, 2.2.13-1, 2.2.14-1, 2.2.16-1, 2.2.16-1ubuntu0.1~esm1, 2.2.8-1, 2.3.18-2, 2.3.20-1, 2.3.20-1ubuntu1, 2.3.8-2, 2.3.8-2ubuntu0.1~esm1
- Fixed versions
- Not specified
- CVEs
- CVE-2026-15561
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 02:03 UTC · Revision 1
Source evidence
A flaw was found in EAP's undertow http/1.1 chunked-transfer decoder. missing limits on size and count would allow an attacker to use an unauthenticated connection to drive the JVM to an OutOfMemory error, stopping all deployments on the listener, and achieving Denial of Service.
osv:UBUNTU-CVE-2026-15561
undertow
Fixed versions: Not specified
undertow
Fixed versions: Not specified
undertow
Fixed versions: Not specified
undertow
Fixed versions: Not specified
undertow
Fixed versions: Not specified
undertow
Fixed versions: Not specified
undertow
Fixed versions: Not specified
Complete source record
{
"id": "3c07e3903af23d647a10e45c15ca638e4bcca29861fb4fff2db6ec2756b374ec",
"url": "https://osv.dev/vulnerability/UBUNTU-CVE-2026-15561",
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"modified": "2026-10-17T12:58:05.889704225Z",
"provider": "osv",
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"references": [
"https://ubuntu.com/security/CVE-2026-15561",
"https://www.cve.org/CVERecord?id=CVE-2026-15561",
"https://bugzilla.redhat.com/show_bug.cgi?id=2483133",
"https://access.redhat.com/errata/RHSA-2026:53644",
"https://access.redhat.com/errata/RHSA-2026:53806",
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"source_id": "core-osv",
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}