CVE-2026-77638

Tor before 0.4.9.11 is prone to a race condition where in just the right circumstances a rendezvous point could man-in-the-middle (impersonate) the onion service that the client was trying to reach.

CVSS v3 8.9 HIGH

8.9^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 6.0

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact LOW

Scope CHANGED

References

Link	Resource
https://gitlab.torproject.org/tpo/core/tor/-/raw/tor-0.4.9.11/ChangeLog	Permissions Required Release Notes Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

16 Sep 2026, 14:08

Type	Values Removed	Values Added
CPE		cpe:2.3:a:torproject:tor::::::::
References	~~() https://gitlab.torproject.org/tpo/core/tor/-/raw/tor-0.4.9.11/ChangeLog -~~	() https://gitlab.torproject.org/tpo/core/tor/-/raw/tor-0.4.9.11/ChangeLog - Permissions Required, Release Notes, Vendor Advisory
First Time		Torproject tor Torproject

Information

Published : 2026-08-20 21:17

Updated : 2026-09-16 14:08

NVD link : CVE-2026-77638

Mitre link : CVE-2026-77638

CVE.ORG link : CVE-2026-77638

JSON object : View

Products Affected

torproject

tor

CWE

CWE-362

Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

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