CVE-2026-77642: tor before 0.4.9.9 (exclusive); +1 more affected products

CVE-2026-77642. CVSS 3.1 base score 9.3 (CRITICAL, NVD). EPSS 0.00353 (percentile 0.27431), scored 17-Oct-2026.

Affected technology

tor · before 0.4.9.9 (exclusive)
torproject

Tor · 0.2.8.2-alpha to before 0.4.9.9
torproject

Description’s affected range: 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

Component: Not specified by the source

Attack conditions (Vendor/CNA, CVSS 3.1): Network (remote) · No privileges required · No user interaction required

Attack conditions (NVD, CVSS 3.1): Network (remote) · No privileges required · No user interaction required

What an attacker can do

Vendor/CNA’s CVSS 3.1 assessment (base score 7.5/10) rates confidentiality impact as none; integrity impact as low; availability impact as high. NVD’s CVSS 3.1 assessment (base score 9.3/10) rates confidentiality impact as none; integrity impact as low; availability impact as high. The description does not specify what an attacker can achieve beyond these rated impacts.

Published 18-Oct-2026 20:24 UTC

CWE: CWE-787
CCR priority: 37.3 /100 (P4)
CVSS 3.1: 9.3 /10 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:H · NVD
EPSS: 0.00353 · percentile 0.27431 · 2026-10-17
KEV: no

Provenance

NVD CVE API 2.0 · Source record · observed 2026-10-18 20:23:06.032219+00:00 UTC

Stable permalink: https://cybercodered.org/item/cve-cve-2026-77642.html