CVE-2026-77638

EUVD-2026-63647
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.
Race Condition
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
mitreCNA
8.9 HIGH
NETWORK
HIGH
NONE
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:L
Base Score
CVSS 3.x
EPSS Score
Percentile: Unknown
Early Detection
Affected products identified ahead of NVD analysis through intelligence sources.
VendorProductVersionSource
torprojecttor
𝑥
< 0.4.9.11
CNA
Common Weakness Enumeration
References
https://gitlab.torproject.org/tpo/core/tor/-/raw/tor-0.4.9.11/ChangeLog