CVE-2026-77584

HIGH CVSS 3.1: 8.2 EPSS 0.25%
Updated Sep 16, 2026
Tor
Parameter Value
CVSS 8.2 (HIGH)
Affected Versions 0.4.8.1-alpha — 0.4.9.10
Fixed In 0.4.9.10
Type CWE-821
Vendor Tor
Public PoC No

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.

Attack Parameters

Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Privileges Required
None
No privileges needed
User Interaction
None
No user interaction needed

Impact Assessment

Confidentiality
None
No data leak
Integrity
High
Complete data modification
Availability
Low
Partial disruption

CVSS Vector v3.1

Weakness Type (CWE)

Vulnerable Products 1

Configuration From (including) Up to (excluding)
Torproject Tor
cpe:2.3:a:torproject:tor:*:*:*:*:*:*:*:*
0.4.8.1-alpha 0.4.9.10