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TI-2021-13568 Aliases CVE-2021-34549GHSA-qx32-4xrf-2j53

An issue was discovered in Tor before 0.4.6.5, aka TROVE-2021-005.

Priority LOW 36CWE-400Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-400.

Summary

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.

Why it matters now

EPSS 0.01608 76th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
——all versions—No fix listedCNA
  • — Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:torproject:tor:*:*:*:*:*:*:*:*before 0.3.5.15; 0.4.0.0 to before 0.4.4.9; 0.4.5.0 to before 0.4.5.9; 0.4.6.0 to before 0.4.6.5Vulnerabletorproject
  • cpe:2.3:a:torproject:tor:*:*:*:*:*:*:*:* Versions before 0.3.5.15; 0.4.0.0 to before 0.4.4.9; 0.4.5.0 to before 0.4.5.9; 0.4.6.0 to before 0.4.6.5 Vulnerable ·torproject

Remediation

No fixed version listed by the sources yet.

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-34549
  2. 2026-10-03 Alias added: GHSA-qx32-4xrf-2j53

References

  • TI-2016-07433 Use after free in Mozilla Firefox KEVCVSS 3.1HIGH 7.5
  • TI-2023-09419 The SafeSocks option in Tor before 0.4.7.13 has a logic error in which the unsafe SOCKS4… CVSS 3.1MEDIUM 6.5
  • TI-2018-00448 Use after free in Tor CVSS 3.0HIGH 7.5
  • TI-2026-54108 Race condition in torproject Tor CVSS 3.1CRITICAL 9.0
  • TI-2026-54112 Out-of-bounds write in torproject Tor CVSS 3.1CRITICAL 9.3
  • TI-2026-32508 Tor before 0.4.9.7 has an out-of-bounds read when an END, a TRUNCATE, or a TRUNCATED cell… CVSS 3.1CRITICAL 9.1
See all 47 →

Sources