CVE-2026-33555
An issue was discovered in HAProxy before 3.3.6. The HTTP/3 parser does not check that the received body length matches a previously announced content-length when the stream is closed via a frame with an empty payload. This can cause desynchronization issues with the backend server and could be used for request smuggling. The earliest affected version is 2.6.
CVE-2026-33555
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-2026-33555
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
Structured affected-version data
Original package identities and version rules from this source.
[
{
"vendor": "HAProxy",
"product": "HAProxy",
"versions": [
{
"status": "affected",
"version": "2.6",
"lessThan": "3.3.6",
"versionType": "custom"
}
],
"defaultStatus": "unaffected"
}
]- Related CVEs
- CVE-2026-33555
Source reference:
/cveMetadata/cveId
Publisher severity
medium
Source reference: /containers/cna/metrics
- Event
- #34752 · Revision 1
- Added to Heist Feed
- Publisher date