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TI-2025-03961 Aliases CVE-2025-4444GHSA-qc3c-vmf8-hgcj

Tor Onion Service Descriptor resource consumption

Priority MEDIUM 61CWE-400Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
High
Attack requirements
None
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · Low
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-400.

Summary

A security flaw has been discovered in Tor up to 0.4.7.16/0.4.8.17. Impacted is an unknown function of the component Onion Service Descriptor Handler. Performing manipulation results in resource consumption. The attack may be initiated remotely. The attack's complexity is rated as high. The exploitability is considered difficult. Upgrading to version 0.4.8.18 and 0.4.9.3-alpha is recommended to address this issue. It is recommended to upgrade the affected component.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00475 41st percentileScored 2026-11-07
Fix Fixed Tor: 0.4.8.18, 0.4.9.3-alpha

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
—Tor0.4.7.0; 0.4.7.1; 0.4.7.2; 0.4.7.3; 0.4.7.4; 0.4.7.5; 0.4.7.6; 0.4.7.7; 0.4.7.8; 0.4.7.9; 0.4.7.10; 0.4.7.11; 0.4.7.12; 0.4.7.13; 0.4.7.14; 0.4.7.15; 0.4.7.16; 0.4.8.0; 0.4.8.1; 0.4.8.2; 0.4.8.3; 0.4.8.4; 0.4.8.5; 0.4.8.6; 0.4.8.7; 0.4.8.8; 0.4.8.9; 0.4.8.10; 0.4.8.11; 0.4.8.12; 0.4.8.13; 0.4.8.14; 0.4.8.15; 0.4.8.16; 0.4.8.170.4.8.18, 0.4.9.3-alphaPatch availableCNA
  • Tor Vendor— Affected 0.4.7.0; 0.4.7.1; 0.4.7.2; 0.4.7.3; 0.4.7.4; 0.4.7.5; 0.4.7.6; 0.4.7.7; 0.4.7.8; 0.4.7.9; 0.4.7.10; 0.4.7.11; 0.4.7.12; 0.4.7.13; 0.4.7.14; 0.4.7.15; 0.4.7.16; 0.4.8.0; 0.4.8.1; 0.4.8.2; 0.4.8.3; 0.4.8.4; 0.4.8.5; 0.4.8.6; 0.4.8.7; 0.4.8.8; 0.4.8.9; 0.4.8.10; 0.4.8.11; 0.4.8.12; 0.4.8.13; 0.4.8.14; 0.4.8.15; 0.4.8.16; 0.4.8.17 Fixed in 0.4.8.18, 0.4.9.3-alpha Patch available CNA

Remediation

  • Fix · CNA Tor Fixed in 0.4.8.18, 0.4.9.3-alpha

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-2025-4444
  2. 2026-10-03 Alias added: GHSA-qc3c-vmf8-hgcj

References

Patch 1

Other 2

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences