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VULNERABILITIES

CVE-2026-77639 Details

Description

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.

Metrics

CVSS 3.x Severity and Vector Strings:

CNA: [email protected]CVSS-B:5.3 MEDIUMVector:CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

References to Advisories, Solutions, and Tools

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URLSource(s)Tag(s)
https://gitlab.torproject.org/tpo/core/tor/-/raw/tor-0.4.9.9/ChangeLog [email protected]Release NotesVendor Advisory

Weakness Enumeration

CWE-IDCWE NameSource
CWE-420Unprotected Alternate Channel[email protected]

Affected Products

ProductVersions
torproject tor
< 0.4.9.9

CPE

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

Remediation

  • No remediation found in references.

Change History

3 change records found show changes

QUICK INFO

CVE Dictionary Entry:
CVE-2026-77639
NVD Published Date:
Aug 20, 2026
NVD Last Modified:
Sep 8, 2026
Source:
[email protected]
CVE-2026-77639 Details - Not Deferred