Description
Tor 0.3.x before 0.3.0.9 has a guard-selection algorithm that only considers the exit relay (not the exit relay's family), which might allow remote attackers to defeat intended anonymity properties by leveraging the existence of large families.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| — | Tor | Tor | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | tor | 0.4.6.7-2.2 | openSUSE-SU-2024:11469-1 |
Advisories 1
- openSUSE-SU-2024:11469-1 tor-0.4.6.7-2.2 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
References
- https://trac.torproject.org/projects/tor/ticket/22753
- https://security-tracker.debian.org/CVE-2017-0377
- https://blog.torproject.org/blog/tor-0309-released-security-update-clients
- https://blog.torproject.org/blog/tor-0314-alpha-released-security-update-clients
- https://github.com/torproject/tor/commit/665baf5ed5c6186d973c46cdea165c0548027350