CVE-2026-77642

EUVD-2026-63665
tor before 0.4.9.9 was prone to an out-of-bounds write when parsing a consensus or  detached signature with unexpected signature digest type. Impact  is minor for most Tor roles, but potentially major for directory   authorities. This is TROVE-2026-019.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
mitreCNA
7.5 HIGH
NETWORK
HIGH
NONE
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:H
Base Score
CVSS 3.x
EPSS Score
Percentile: Unknown
Early Detection
Affected products identified ahead of NVD analysis through intelligence sources.
VendorProductVersionSource
torprojecttor
𝑥
< 0.4.9.9
CNA
Common Weakness Enumeration
References
https://gitlab.torproject.org/tpo/core/tor/-/raw/tor-0.4.9.9/ChangeLog