CVE-2020-8516

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Published Feb 2, 2020 CVSS 3.1 · 5.3 Medium EPSS 2.5% KEV · Not listed

Description

The daemon in Tor through 0.4.1.8 and 0.4.2.x through 0.4.2.6 does not verify that a rendezvous node is known before attempting to connect to it, which might make it easier for remote attackers to discover circuit information. NOTE: The network team of Tor claims this is an intended behavior and not a vulnerability

Affected Products

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

n/a

n/a

affected

Version	Status	Constraints
`n/a`	affected	—

Configuration 1 [-]

OR	cpe:2.3:a:torproject:tor::::::::
	cpe:2.3:a:torproject:tor::::::::

No data.

No data available yet.

Remediation

No solution or workaround provided in the CVE record

Tracking

Sign in to view the affected projects.

Advisories

No advisories available

Metrics

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact Low

Integrity Impact None

Availability Impact None

User Interaction None

No CVSS v3.0

Access Vector Network

Access Complexity Low

Authentication None

Confidentiality Impact Partial

Integrity Impact None

Availability Impact None

This CVE is not in the KEV list.

Exploit prediction score: 2.5% (2.499% probability within 30 days)

Key SSVC decision points have not yet been added.

References

Link	Providers
https://lists.torproject.org/pipermail/tor-dev/2020-February/014146.html
https://lists.torproject.org/pipermail/tor-dev/2020-February/014147.html
https://security-tracker.debian.org/tracker/CVE-2020-8516
https://trac.torproject.org/projects/tor/ticket/33129
https://www.hackerfactor.com/blog/index.php?/archives/868-Deanonymizing-Tor-Circuits.html

History

No history.

Subscriptions

Torproject Tor

Weaknesses

NVD-CWE-noinfo

Sources

CVE record Updated: Aug 4, 2024, 10:03 AM

Status: PUBLISHED
Assigner: mitre
Published: Feb 2, 2020, 12:52 PM
Updated: Aug 4, 2024, 10:03 AM
Reserved: Feb 2, 2020, 12:00 AM

View source JSON

Vulnrichment No data

No data.

NVD Updated: Jun 17, 2026, 3:26 AM

Status: Modified
Published: Feb 2, 2020, 1:15 PM
Modified: Jun 17, 2026, 3:26 AM

View source JSON

Red Hat No data

No data.

OpenCVE enrichment No data

No data.

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