CVE-2026-77639
CVSS Score
5.3
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-420 |
| Vendor | torproject |
| Product | tor |
| Published | Aug 20, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
Low
Affected Versions
torproject / Tor
0.3.1.1-alpha < 0.4.9.9