CVE-2011-4896

CVE-2011-4896 is a medium-severity vulnerability in Tor with a CVSS 2.0 base score of 4.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-200.

Key facts

Description

Tor before 0.2.2.24-alpha continues to use a reachable bridge that was previously configured but is not currently configured, which might allow remote attackers to obtain sensitive information about clients in opportunistic circumstances by monitoring network traffic to the bridge port.

Frequently asked questions

What is CVE-2011-4896?
Tor before 0.2.2.24-alpha continues to use a reachable bridge that was previously configured but is not currently configured, which might allow remote attackers to obtain sensitive information about clients in opportunistic circumstances by monitoring network traffic to the bridge port.
How severe is CVE-2011-4896?
CVE-2011-4896 has a CVSS 2.0 base score of 4.3, rated medium severity.
Is CVE-2011-4896 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2011-4896?
CVE-2011-4896 primarily affects Tor. In total, 226 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2011-4896?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2011-4896 published?
CVE-2011-4896 was published on 2011-12-23 and last updated on 2026-06-16.

References

Affected products (226)

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