CVE-2026-33555_CVE-2026-33555

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MEDIUM

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:N

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.

Basic Information

ID CVE-2026-33555

Source mitre

Published Apr 13, 2026 at 00:00

Modified Apr 13, 2026 at 16:22

Affected Product

Vendor HAProxy

Product HAProxy

Version 2.6

Affected Versions HAProxy HAProxy 2.6

CWE Classification

CWE-130

References

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    "published": "2026-04-13T00:00:00.000Z",
    "modified": "2026-04-13T16:22:13.958Z",
    "type": "cve",
    "title": "CVE-2026-33555",
    "source": "mitre",
    "references": "https://www.haproxy.org\nhttps://www.haproxy.com/documentation/haproxy-aloha/changelog/\nhttps://github.com/haproxy/haproxy/commit/05a295441c621089ffa4318daf0dbca2dd756a84\nhttps://www.mail-archive.com/[email protected]/msg46752.html",
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