CVE-2011-0493

CVE-2011-0493 is a medium-severity vulnerability in Tor with a CVSS 2.0 base score of 5.0. 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-189.

Key facts

Description

Tor before 0.2.1.29 and 0.2.2.x before 0.2.2.21-alpha might allow remote attackers to cause a denial of service (assertion failure and daemon exit) via vectors related to malformed router caches and improper handling of integer values.

Frequently asked questions

What is CVE-2011-0493?
Tor before 0.2.1.29 and 0.2.2.x before 0.2.2.21-alpha might allow remote attackers to cause a denial of service (assertion failure and daemon exit) via vectors related to malformed router caches and improper handling of integer values.
How severe is CVE-2011-0493?
CVE-2011-0493 has a CVSS 2.0 base score of 5.0, rated medium severity.
Is CVE-2011-0493 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (83rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2011-0493?
CVE-2011-0493 primarily affects Tor. In total, 207 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2011-0493?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2011-0493 published?
CVE-2011-0493 was published on 2011-01-19 and last updated on 2026-06-16.

References

Affected products (207)

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