PatchTheCVECVE-2009-0654: Tor 0.2.0.28, and probably 0.2.0.34 and earlier, allows remote attackers, with control of an entry router and
CVE-2009-0654 is a medium-severity flaw (CVSS 5.1) affecting tor. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
Tor 0.2.0.28, and probably 0.2.0.34 and earlier, allows remote attackers, with control of an entry router and an exit router, to confirm that a sender and receiver are communicating via vectors involving (1) replaying, (2) modifying, (3) inserting, or (4) deleting a single cell, and then observing cell recognition errors at the exit router. NOTE: the vendor disputes the significance of this issue, noting that the product's design "accepted end-t
Why this priority
- Public exploit reference
A fixed release or distro patch exists.
Risk facts
| CVSS score | 5.1 (Medium) |
| EPSS exploit chance | 2.4% (top 16%) |
| CISA exploited list | No |
| Published | 2009-02-20 |
| Last modified | 2026-06-16 |
Last updated 2026-06-16 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2009-0654?
tor: upgrade to newer than 0.2.0.34. Exact commands for each OS are on this page.
Is CVE-2009-0654 being exploited?
CVE-2009-0654 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2009-0654 affect?
CVE-2009-0654 affects tor. Severity is medium (CVSS 5.1). Tor 0.2.0.28, and probably 0.2.0.34 and earlier, allows remote attackers, with control of an entry router and an exit router, to confirm that a sender and receiver are communicating via vectors involving (1) replaying, (2) modifying, (3) in
How urgent is CVE-2009-0654?
Priority 44/100. Public exploit reference
Related CVEs
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