What’s Vulnerable › Vulnerabilities
CVE-2017-8820
- Severity: high (CVSS 7.5 v3.0)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 1.7% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2017-12-03 · updated 2026-06-17
- Weakness: CWE-476
Description
In Tor before 0.2.5.16, 0.2.6 through 0.2.8 before 0.2.8.17, 0.2.9 before 0.2.9.14, 0.3.0 before 0.3.0.13, and 0.3.1 before 0.3.1.9, remote attackers can cause a denial of service (NULL pointer dereference and application crash) against directory authorities via a malformed descriptor, aka TROVE-2017-010.
Affected products
- Debian Linux: 8.0, 9.0
- Tor Project Tor: before 0.2.5.16; from 0.2.6 before 0.2.8.17; from 0.2.9 before 0.2.9.14; from 0.3.0 before 0.3.0.13; from 0.3.1 before 0.3.1.9 — fixed in 0.2.5.16, 0.2.8.17, 0.2.9.14, 0.3.0.13, 0.3.1.9
How to fix
Upgrade to a fixed version: Tor Project Tor 0.2.5.16, 0.2.8.17, 0.2.9.14, 0.3.0.13. Check the vendor advisory for mitigations.
References
- https://blog.torproject.org/new-stable-tor-releases-security-fixes-0319-03013-02914-02817-02516
- https://bugs.torproject.org/24245
- https://www.debian.org/security/2017/dsa-4054
- https://blog.torproject.org/new-stable-tor-releases-security-fixes-0319-03013-02914-02817-02516
- https://bugs.torproject.org/24245
- https://www.debian.org/security/2017/dsa-4054
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