CVE-2011-4897

CVE-2011-4897 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 0.2.2.25-alpha, when configured as a relay without the Nickname configuration option, uses the local hostname as the Nickname value, which allows remote attackers to obtain potentially sensitive information by reading this value.

Frequently asked questions

What is CVE-2011-4897?
Tor before 0.2.2.25-alpha, when configured as a relay without the Nickname configuration option, uses the local hostname as the Nickname value, which allows remote attackers to obtain potentially sensitive information by reading this value.
How severe is CVE-2011-4897?
CVE-2011-4897 has a CVSS 2.0 base score of 4.3, rated medium severity.
Is CVE-2011-4897 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-2011-4897?
CVE-2011-4897 primarily affects Tor. In total, 227 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2011-4897?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2011-4897 published?
CVE-2011-4897 was published on 2011-12-23 and last updated on 2026-06-16.

References

Affected products (227)

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