CVE-2025-55702

When a client sends a POST with Expect: 100-continue and the origin answers before reading the body, Apache Traffic Server parses the unread body left on the client connection as the next request. An attacker behind a front-end proxy that shares connections to Traffic Server can use this to smuggle requests past the front end and desynchronize responses for other users. This issue affects Apache Traffic Server: from 8.0.0 through 8.1.11, from 9.0.0 through 9.2.15, from 10.0.0 through 10.1.4, 10.2.0. Users are recommended to upgrade to version 9.2.16, 10.1.5, or 10.2.1, which fix the issue.

CVSS v3 8.7 HIGH

8.7^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 5.8

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://lists.apache.org/thread/r95dq29ywcd1f4x30snxlqmb12z4s4kc

Configurations

No configuration.

History

28 Oct 2026, 14:10

Type	Values Removed	Values Added
Summary		(es) Cuando un cliente envía un POST con?Expect:?100-continue y el origen responde antes de leer el cuerpo, Apache Traffic Server interpreta el cuerpo no leído que queda en la conexión del cliente como la siguiente solicitud. Un atacante detrás de un proxy front-end que comparte conexiones con Traffic Server puede usar esto para infiltrar solicitudes más allá del front?end y desincronizar respuestas para otros usuarios.\n\nEste problema afecta a Apache Traffic Server: desde la versión?8.0.0 hasta la?8.1.11 incluida, desde la versión?9.0.0 hasta la?9.2.15 incluida, desde la versión?10.0.0 hasta la?10.1.4 incluida y la versión?10.2.0.\n\nSe recomienda a los usuarios actualizar a la versión?9.2.16,?10.1.5?o?10.2.1, que corrigen el problema.

21 Oct 2026, 19:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-21 19:16

Updated : 2026-10-28 14:10

NVD link : CVE-2025-55702

Mitre link : CVE-2025-55702

CVE.ORG link : CVE-2025-55702

JSON object : View

Products Affected

No product.

CWE

CWE-444

Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')

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