CVE-2021-39246

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Summary

CVECVE-2021-39246
StatePUBLIC
Assigner[email protected]
Source PriorityCVE Program / NVD first with legacy fallback
Published2021-09-24 19:15:00 UTC
Updated2021-10-01 13:00:00 UTC
DescriptionTor Browser through 10.5.6 and 11.x through 11.0a4 allows a correlation attack that can compromise the privacy of visits to v2 onion addresses. Exact timestamps of these onion-service visits are logged locally, and an attacker might be able to compare them to timestamp data collected by the destination server (or collected by a rogue site within the Tor network).

Risk And Classification

Problem Types: CWE-532

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Operating System Apple Macos - All All All
Operating System Linux Linux Kernel - All All All
Operating System Microsoft Windows - All All All
Application Torproject Tor Browser 11.0 alpha2 All All
Application Torproject Tor Browser 11.0 alpha4 All All
Application Torproject Tor Browser All All All All

References

ReferenceSourceLinkTags
Update connection_edge.c (!434) · Merge requests · The Tor Project / Core / Tor · GitLab MISC gitlab.torproject.org
TOR Vulnerability Allows Attackers to View Exact Timestamp a User Connected to a v2 Onion Address - Privacy Affairs MISC www.privacyaffairs.com
security/SICK-2021-111.md at master · sickcodes/security · GitHub MISC github.com
CVE-2021-39246 - Tor Browser through 10.5.6 and 11.x through 11.0a4 allows a correlation attack excessive verbose logging - Windows, macOS, Linux - Sick Codes - Security Research, Hardware & Software Hacking, Consulting, Linux, IoT, Cloud, Embedded, Arch, Tweaks & Tips! MISC sick.codes
Log warning when connecting to soon-to-be-deprecated v2 onions. (80c404c4) · Commits · The Tor Project / Core / Tor · GitLab MISC gitlab.torproject.org
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis
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