// For flags

CVE-2025-7054

Infinite loop triggered by connection ID retirement

Severity Score

8.7
*CVSS v4

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

Attend
*SSVC
Descriptions

Cloudflare quiche was discovered to be vulnerable to an infinite loop when sending packets containing RETIRE_CONNECTION_ID frames. QUIC connections possess a set of connection identifiers (IDs); see Section 5.1 of RFC 9000 https://datatracker.ietf.org/doc/html/rfc9000#section-5.1 . Once the QUIC handshake completes, a local endpoint is responsible for issuing and retiring Connection IDs that are used by the remote peer to populate the Destination Connection ID field in packets sent from remote to local. Each Connection ID has a sequence number to ensure synchronization between peers. An unauthenticated remote attacker can exploit this vulnerability by first completing a handshake and then sending a specially-crafted set of frames that trigger a connection ID retirement in the victim. When the victim attempts to send a packet containing RETIRE_CONNECTION_ID frames, Section 19.16 of RFC 9000 https://datatracker.ietf.org/doc/html/rfc9000#section-19.6 requires that the sequence number of the retired connection ID must not be the same as the sequence number of the connection ID used by the packet. In other words, a packet cannot contain a frame that retires itself. In scenarios such as path migration, it is possible for there to be multiple active paths with different active connection IDs that could be used to retire each other. The exploit triggered an unintentional behaviour of a quiche design feature that supports retirement across paths while maintaining full connection ID synchronization, leading to an infinite loop.This issue affects quiche: from 0.15.0 before 0.24.5.

Se descubrió que Cloudflare Quiche era vulnerable a un bucle infinito al enviar paquetes que contenían tramas RETIRE_CONNECTION_ID. Las conexiones QUIC poseen un conjunto de identificadores de conexión (ID); consulte la Sección 5.1 de RFC 9000 (https://datatracker.ietf.org/doc/html/rfc9000#section-5.1). Una vez completado el protocolo de enlace QUIC, un endpoint local se encarga de emitir y retirar los ID de conexión que utiliza el punto remoto para rellenar el campo ID de conexión de destino en los paquetes enviados desde el punto remoto al local. Cada ID de conexión tiene un número de secuencia para garantizar la sincronización entre los puntos. Un atacante remoto no autenticado puede explotar esta vulnerabilidad completando primero un protocolo de enlace y luego enviando un conjunto de tramas especialmente manipuladas que desencadenan el retiro del ID de conexión en la víctima. Cuando la víctima intenta enviar un paquete que contiene tramas RETIRE_CONNECTION_ID, la Sección 19.16 de RFC 9000 (https://datatracker.ietf.org/doc/html/rfc9000#section-19.6) exige que el número de secuencia del ID de conexión retirado no coincida con el del ID de conexión utilizado por el paquete. En otras palabras, un paquete no puede contener una trama que se retire a sí misma. En escenarios como la migración de rutas, es posible que existan múltiples rutas activas con diferentes ID de conexión activos que podrían utilizarse para retirarse mutuamente. El exploit desencadenó un comportamiento involuntario de una característica de diseño de quiche que permite el retiro entre rutas manteniendo la sincronización completa del ID de conexión, lo que provocó un bucle infinito. Este problema afecta a quiche desde la versión 0.15.0 hasta la 0.24.5.

*Credits: N/A
CVSS Scores
Attack Vector
Network
Attack Complexity
Low
Attack Requirements
None
Privileges Required
None
User Interaction
None
System
Vulnerable | Subsequent
Confidentiality
None
None
Integrity
None
None
Availability
High
None
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
Attack Vector
Network
Attack Complexity
Low
Authentication
None
Confidentiality
None
Integrity
None
Availability
Partial
* Common Vulnerability Scoring System
SSVC
  • Decision:Attend
Exploitation
None
Automatable
Yes
Tech. Impact
Partial
* Organization's Worst-case Scenario
Timeline
  • 2025-07-03 CVE Reserved
  • 2025-08-07 CVE Published
  • 2025-08-07 CVE Updated
  • 2025-08-15 EPSS Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
  • CWE-835: Loop with Unreachable Exit Condition ('Infinite Loop')
CAPEC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Cloudflare
Search vendor "Cloudflare"
 Quiche
Search vendor "Cloudflare" for product "Quiche"
 >= 0.15.0 < 0.24.5
Search vendor "Cloudflare" for product "Quiche" and version " >= 0.15.0 < 0.24.5"
en
Affected