Vulnerability Details 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.
Exploit prediction scoring system (EPSS) score
EPSS Score 0.002
EPSS Ranking 15.8%
CVSS Severity
CVSS v3 Score 5.3