CVE-2021-34549
HIGHCVSS 7.5/10EPSS 1.61%
Last modified
CVE-2021-34549 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. An issue was discovered in Tor before 0.4.6.5, aka TROVE-2021-005. Hashing is mishandled for certain retrieval of circuit data. EPSS estimates a 1.61% chance of exploitation in the next 30 days.
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.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Torproject | Tor | < 0.3.5.15 |
| Torproject | Tor | >= 0.4.0.0, < 0.4.4.9 |
| Torproject | Tor | >= 0.4.5.0, < 0.4.5.9 |
| Torproject | Tor | >= 0.4.6.0, < 0.4.6.5 |
References
- https://blog.torproject.org/node/2041Release Notes, Vendor Advisory
- https://security.gentoo.org/glsa/202107-25Third Party Advisory
- https://blog.torproject.org/node/2041Release Notes, Vendor Advisory
- https://security.gentoo.org/glsa/202107-25Third Party Advisory
Timeline
- Published
- Last Modified
- Status
- Modified
Frequently Asked Questions
What is CVE-2021-34549?
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.
How severe is CVE-2021-34549?
CVE-2021-34549 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 1.61% probability of exploitation in the next 30 days.
How do I fix CVE-2021-34549?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.
How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
- Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
- PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
- AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.
Related CVEs from 2021
- CVE-2021-34540Advantech WebAccess 8.4.2 and 8.4.4 allows XSS via the usern…6.1
- CVE-2021-34543The web administration server in Solar-Log 500 before 2.8.2 …7.5
- CVE-2021-34544An issue was discovered in Solar-Log 500 before 2.8.2 Build …6.5
- CVE-2021-34546An unauthenticated attacker with physical access to a comput…6.8
- CVE-2021-34547PRTG Network Monitor 20.1.55.1775 allows /editsettings CSRF …4.3
- CVE-2021-34548An issue was discovered in Tor before 0.4.6.5, aka TROVE-202…7.5
- CVE-2021-3455Disconnecting L2CAP channel right after invalid ATT request …7.5
- CVE-2021-34550An issue was discovered in Tor before 0.4.6.5, aka TROVE-202…7.5
- CVE-2021-34551PHPMailer before 6.5.0 on Windows allows remote code executi…8.1
- CVE-2021-34552Pillow through 8.2.0 and PIL (aka Python Imaging Library) th…9.8
- CVE-2021-34553Sonatype Nexus Repository Manager 3.x before 3.31.0 allows a…4.3
- CVE-2021-34555OpenDMARC 1.4.1 and 1.4.1.1 allows remote attackers to cause…7.5
Are you affected by CVE-2021-34549?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST