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Vulnerability record · CVE-2011-4895 · published 23 December 2011

CVE-2011-4895: Tor information exposure vulnerability

Tor · Tor

Tor before 0.2.2.34, when configured as a bridge, sets up circuits through a process different from the process used by a client, which makes it easier for remote attackers to enumerate bridges by observing circuit building.

4.3 CVSS 2.0 Medium EPSS 1.5% · top 26.3% CWE-200 · Information exposure
4.3CVSS 2.0 base score
1.5%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
2References
16 Jun 2026Last modified by NVD

Description

Tor before 0.2.2.34, when configured as a bridge, sets up circuits through a process different from the process used by a client, which makes it easier for remote attackers to enumerate bridges by observing circuit building.

AV:N/AC:M/Au:N/C:P/I:N/A:N

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://blog.torproject.org/blog/tor-02234-released-security-patches PatchVendor Advisory
https://blog.torproject.org/blog/tor-02234-released-security-patches PatchVendor Advisory

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2011-4895), CISA KEV, FIRST EPSS (scores of 2026-09-30). This page is refreshed as NVD updates the record.