CVE-2026-77639

Tor before 0.4.9.9 was prone to a compression bomb bypass where an attacker could concatenate many gzip or zlib sub-streams, each just under the per-stream detection threshold, to avoid the compression bomb check entirely. This is TROVE-2026-022.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://gitlab.torproject.org/tpo/core/tor/-/raw/tor-0.4.9.9/ChangeLog	Release Notes Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

18 Oct 2026, 20:10

Type	Values Removed	Values Added
Summary		(es) Tor anterior a la versión 0.4.9.9 era propenso a una elusión de la bomba de compresión donde un atacante podía concatenar muchos sub-flujos gzip o zlib, cada uno justo por debajo del umbral de detección por flujo, para evitar por completo la verificación de la bomba de compresión. Esto es TROVE-2026-022.

Information

Published : 2026-08-20 21:17

Updated : 2026-10-18 20:10

NVD link : CVE-2026-77639

Mitre link : CVE-2026-77639

CVE.ORG link : CVE-2026-77639

JSON object : View

Products Affected

torproject

tor

CWE

CWE-420

Unprotected Alternate Channel

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