Description
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.
CVSS Metrics
- Vector
- CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:N
- Attack Vector
- network
- Complexity
- high
- Privileges
- none
- User Action
- none
- Scope
- changed
- Confidentiality
- none
- Integrity
- low
- Availability
- none
- Weaknesses
- CWE-130
Metadata
- Primary Vendor
- UNKNOWN
- Published
- 4/13/2026
- Last Modified
- 4/13/2026
- Source
- NIST NVD
- Note: Verify all details with official vendor sources before applying patches.
Affected Products
No affected products information available.
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