5.3Medium
CVE-2026-77639
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.
Weakness (CWE):
CWE-420
Data: CVE.org, NVD, CISA KEV, FIRST EPSS, Ubuntu. Published as the sources state it, in English.
Affected products and versions
| Vendor | Product | Versions | |
|---|---|---|---|
| torproject | Tor | 0.3.1.1-alpha – < 0.4.9.9 |
References and patches
- https://gitlab.torproject.org/tpo/core/tor/-/raw/tor-0.4.9.9/ChangeLog Release NotesVendor Advisory
CPE matches (NVD) (1)
cpe:2.3:a:torproject:tor:*:*:*:*:*:*:*:*< 0.4.9.9