CVE-2021-34549

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Published Jun 29, 2021 CVSS 3.1 · 7.5 High EPSS 1.6% KEV · Not listed

Description

An issue was discovered in Tor before 0.4.6.5, aka TROVE-2021-005. Hashing is mishandled for certain retrieval of circuit data. Consequently. an attacker can trigger the use of an attacker-chosen circuit ID to cause algorithm inefficiency.

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::::::::
	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

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Advisories

Source	ID	Title
Debian DSA	DSA-4932-1	tor security update
EUVD	EUVD-2021-21201	An issue was discovered in Tor before 0.4.6.5, aka TROVE-2021-005. Hashing is mishandled for certain retrieval of circuit data. Consequently. an attacker can trigger the use of an attacker-chosen circuit ID to cause algorithm inefficiency.
Ubuntu USN	USN-5036-1	Tor vulnerabilities

Metrics

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact High

User Interaction None

No CVSS v3.0

Access Vector Network

Access Complexity Low

Authentication None

Confidentiality Impact None

Integrity Impact None

Availability Impact Partial

This CVE is not in the KEV list.

Exploit prediction score: 1.6% (1.608% probability within 30 days)

Key SSVC decision points have not yet been added.

References

Link	Providers
https://blog.torproject.org/node/2041
https://gitlab.torproject.org/tpo/core/tor/-/issues/40391
https://security.gentoo.org/glsa/202107-25

History

No history.

Subscriptions

Torproject Tor

Weaknesses

CWE-400

Sources

CVE record Updated: Aug 4, 2024, 12:12 AM

Status: PUBLISHED
Assigner: mitre
Published: Jun 29, 2021, 11:08 AM
Updated: Aug 4, 2024, 12:12 AM
Reserved: Jun 10, 2021, 12:00 AM

View source JSON

Vulnrichment No data

No data.

NVD Updated: Jun 17, 2026, 3:56 AM

Status: Modified
Published: Jun 29, 2021, 12:15 PM
Modified: Jun 17, 2026, 3:56 AM

View source JSON

Red Hat No data

No data.

OpenCVE enrichment No data

No data.

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