CVE-2026-77584

Tor before 0.4.9.10 did not reject a CONFLUX_LINK cell that arrives on a circuit which already has attached streams. A malicious client could send a RELAY_COMMAND_BEGIN before the CONFLUX_LINK on the same circuit, attaching an exit stream that would later end up orphan leaving a dangling circuit back-pointer and a use-after-free (UAF) when the circuit is freed. This is TROVE-2026-025.

CVSS v3 7.0 HIGH

7.0^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 4.7

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact HIGH

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://gitlab.torproject.org/tpo/core/tor/-/raw/tor-0.4.9.10/ChangeLog	Release Notes Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:torproject:tor:*:*:*:*:*:*:*:*

History

18 Oct 2026, 20:10

Type	Values Removed	Values Added
Summary		(es) Tor antes de la versión 0.4.9.10 no rechazaba una celda CONFLUX_LINK que llegaba a un circuito que ya tenía flujos adjuntos. Un cliente malicioso podría enviar un RELAY_COMMAND_BEGIN antes del CONFLUX_LINK en el mismo circuito, adjuntando un flujo de salida que más tarde terminaría huérfano, dejando un puntero de retorno de circuito colgante y un uso después de liberación (UAF) cuando el circuito es liberado. Esto es TROVE-2026-025.

16 Sep 2026, 14:15

Type	Values Removed	Values Added
CPE		cpe:2.3:a:torproject:tor::::::::
First Time		Torproject tor Torproject
References	~~() https://gitlab.torproject.org/tpo/core/tor/-/raw/tor-0.4.9.10/ChangeLog -~~	() https://gitlab.torproject.org/tpo/core/tor/-/raw/tor-0.4.9.10/ChangeLog - Release Notes, Vendor Advisory

Information

Published : 2026-08-20 21:17

Updated : 2026-10-18 20:10

NVD link : CVE-2026-77584

Mitre link : CVE-2026-77584

CVE.ORG link : CVE-2026-77584

JSON object : View

Products Affected

torproject

tor

CWE

CWE-821

Incorrect Synchronization

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