CVE-2026-110354
HAProxy 3 before 3.4.6 allows a remote unauthenticated attacker to cause a denial of service (persistent worker-thread CPU exhaustion) via an HTTP/1.1 chunked request. Although the H1 multiplexer drains the request before closing the stream, the parser repeatedly re-processes the same bytes without making progress. The affected thread stays busy at 100% CPU after timeouts expire and after the client disconnects, and repeated requests can consume all worker threads until the process is restarted.
CVE-2026-110354
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-110354
HAProxy
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
HAProxy Enterprise Edition
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
HAProxy Kubernetes Ingress Controller
Source reference: /containers/cna/affected/2/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Kubernetes Ingress Controller Enterprise
Source reference: /containers/cna/affected/3/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://git.haproxy.org/git/haproxy.git",
"vendor": "HAProxy",
"modules": [
"mux-h1"
],
"product": "HAProxy",
"versions": [
{
"status": "affected",
"version": "3.0.0",
"lessThan": "3.0.30",
"versionType": "custom"
},
{
"status": "affected",
"version": "3.2.0",
"lessThan": "3.2.26",
"versionType": "custom"
},
{
"status": "affected",
"version": "3.3.0",
"lessThan": "3.3.17",
"versionType": "custom"
},
{
"status": "affected",
"version": "3.4.0",
"lessThan": "3.4.6",
"versionType": "custom"
},
{
"status": "affected",
"version": "3.5-dev",
"lessThan": "3.5-dev9",
"versionType": "custom"
}
],
"programFiles": [
"src/h1_htx.c"
],
"defaultStatus": "unaffected",
"programRoutines": [
{
"name": "h1_parse_msg_data"
}
]
},
{
"vendor": "HAProxy",
"product": "HAProxy Enterprise Edition",
"versions": [
{
"status": "affected",
"version": "3.0r1",
"lessThan": "3.0r1-362.1441",
"versionType": "custom"
},
{
"status": "affected",
"version": "3.2r1",
"lessThan": "3.2r1-378.1259",
"versionType": "custom"
},
{
"status": "affected",
"version": "3.3r1",
"lessThan": "3.3r1-377.1005",
"versionType": "custom"
}
],
"defaultStatus": "unaffected"
},
{
"vendor": "HAProxy Technologies",
"product": "HAProxy Kubernetes Ingress Controller",
"versions": [
{
"status": "affected",
"version": "3.2.0",
"lessThan": "3.2.17",
"versionType": "custom"
}
],
"defaultStatus": "unaffected"
},
{
"vendor": "HAProxy Technologies",
"product": "Kubernetes Ingress Controller Enterprise",
"versions": [
{
"status": "affected",
"version": "3.2.0",
"lessThan": "3.2.17-ee1",
"versionType": "custom"
},
{
"status": "affected",
"version": "3.0",
"lessThan": "3.0.16-ee17",
"versionType": "custom"
},
{
"status": "affected",
"version": "1.11",
"lessThan": "1.11.14-ee11",
"versionType": "custom"
}
],
"defaultStatus": "unaffected"
}
]- Related CVEs
- CVE-2026-110354
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #52306 · Revision 1
- Added to Heist Feed
- Publisher date