High severity · published Jul 2, 2017
CVE-2017-0377
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…
7.5
CVSS
2.4%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)2.4% · higher than 84% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
TO
Tor · Torproject
0.3.0.1; 0.3.0.2; 0.3.0.3; 0.3.0.4; 0.3.0.5; 0.3.0.6; +2 more · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2017-0377
CVE.org
https://www.cve.org/CVERecord?id=CVE-2017-0377
Release Notes
https://blog.torproject.org/blog/tor-0309-released-security-update-clients
Release Notes
https://blog.torproject.org/blog/tor-0314-alpha-released-security-update-clients
Patch
https://github.com/torproject/tor/commit/665baf5ed5c6186d973c46cdea165c0548027350
Third Party Advisory
https://security-tracker.debian.org/CVE-2017-0377
Issue Tracking
https://trac.torproject.org/projects/tor/ticket/22753
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