CVE-2026-77639CWE-420
CVE-2026-77639
Medium · published August 21, 2026
What it is
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.
The record
Technical detail
- CVSS v3.1
- 5.3 · MEDIUM
- Vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
- CVSS v4.0
- Not supplied
- EPSS
- 0.00246 · 15.8th percentile
- Weakness
- CWE-420 · Unprotected Alternate Channel
- Published
- 2026-08-21T01:17Z
References (1)
EPSS history
Timeline