CVE-2017-8819

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, the replay-cache protection mechanism is ineffective for v2 onion services, aka TROVE-2017-009. An attacker can send many INTRODUCE2 cells to trigger this issue.

Published: 2017-12-03 Last update: 2026-05-13 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2017-8819 is rated Moderate Risk (48.1/100): CVSS High severity, with medium exploitation likelihood (EPSS 0.29%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2017-8819

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-04-09 0.55% 0.29% -0.25%
2 2025-03-30 0.86% 0.55% -0.32%
3 2025-03-29 — 0.86% —

Full EPSS history (7 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2017-8819

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.0 HIGH
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 3.6 [email protected]
5.0 2.0 MEDIUM
AV:N/AC:L/Au:N/C:N/I:N/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:P)
Partial availability impact.
 10.0 2.9 [email protected]

Weakness enumeration for CVE-2017-8819

OS Trackers for CVE-2017-8819

vendor priority summary link
debian not yet assigned CVE-2017-8819 not yet assigned priority: Debian including 1 source packages (tor), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2017-8819
ubuntu medium CVE-2017-8819 medium priority: Ubuntu including 1 source packages (tor), 7 status rows across 7 suites (artful, bionic, cosmic, trusty, upstream, xenial, zesty): released 4, not-affected 2, ignored 1. https://ubuntu.com/security/CVE-2017-8819

Affected software / configurations for CVE-2017-8819

Vendor Product Version Raw CPE
tor_project tor < 0.2.5.16 cpe:2.3:a:tor_project:tor:*:*:*:*:*:*:*:*
tor_project tor >= 0.2.6, < 0.2.8.17 cpe:2.3:a:tor_project:tor:*:*:*:*:*:*:*:*
tor_project tor >= 0.2.9, < 0.2.9.14 cpe:2.3:a:tor_project:tor:*:*:*:*:*:*:*:*
tor_project tor >= 0.3.0, < 0.3.0.13 cpe:2.3:a:tor_project:tor:*:*:*:*:*:*:*:*
tor_project tor >= 0.3.1, < 0.3.1.9 cpe:2.3:a:tor_project:tor:*:*:*:*:*:*:*:*
debian debian_linux 8.0 cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
debian debian_linux 9.0 cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*

References for CVE-2017-8819

cvelogic Threat Intelligence