CVE-2006-6893
CVE-2006-6893 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.
Key facts
- Severity: Medium (CVSS 2.0 base score 5.0)
- EPSS exploit prediction: 2% (80th percentile)
- Actively exploited: Not listed in CISA KEV
- Affected product: Tor
- Published:
- Last modified:
Description
Tor allows remote attackers to discover the IP address of a hidden service by accessing this service at a high rate, thereby changing the server's CPU temperature and consequently changing the pattern of time values visible through (1) ICMP timestamps, (2) TCP sequence numbers, and (3) TCP timestamps, a different vulnerability than CVE-2006-0414. NOTE: it could be argued that this is a laws-of-physics vulnerability that is a fundamental design limitation of certain hardware implementations, so perhaps this issue should not be included in CVE.
Frequently asked questions
- What is CVE-2006-6893?
- Tor allows remote attackers to discover the IP address of a hidden service by accessing this service at a high rate, thereby changing the server's CPU temperature and consequently changing the pattern of time values visible through (1) ICMP timestamps, (2) TCP sequence numbers, and (3) TCP timestamps, a different vulnerability than CVE-2006-0414. NOTE: it could be argued that this is a laws-of-physics vulnerability that is a fundamental design limitation of certain hardware implementations, so perhaps this issue should not be included in CVE.
- How severe is CVE-2006-6893?
- CVE-2006-6893 has a CVSS 2.0 base score of 5.0, rated medium severity.
- Is CVE-2006-6893 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (80th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2006-6893?
- CVE-2006-6893 affects Tor. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2006-6893?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2006-6893 published?
- CVE-2006-6893 was published on 2006-12-31 and last updated on 2026-06-16.
References
- http://events.ccc.de/congress/2006/Fahrplan/events/1513.en.html
- http://www.cl.cam.ac.uk/~sjm217/papers/ccs06hotornot.pdf
- http://www.lightbluetouchpaper.org/2006/09/04/hot-or-not-revealing-hidden-services-by-their-clock-skew/
Affected products (1)
- cpe:2.3:a:tor:tor:0.1.1.26:*:*:*:*:*:*:*
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