CVE-2017-18076

In strategy.rb in OmniAuth before 1.3.2, the authenticity_token value is improperly protected because POST (in addition to GET) parameters are stored in the session and become available in the environment of the callback phase.

Published: 2018-01-26 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2017-18076 is rated Moderate Risk (59.6/100): CVSS High severity, with medium exploitation likelihood (EPSS 2.14%). EPSS rose +1.70% over the last day, indicating growing attacker interest. 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-2017-18076

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 2026-06-15 0.44% 2.14% +1.70%
2 2025-08-12 0.46% 0.44% -0.02%
3 2025-03-30 — 0.46% —

Full EPSS history (9 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2017-18076

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N 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:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 3.6 [email protected]
5.0 2.0 MEDIUM
AV:N/AC:L/Au:N/C:P/I:N/A:N 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:P)
Partial confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:N)
No availability impact.
 10.0 2.9 [email protected]

Weakness enumeration for CVE-2017-18076

GitHub Security Advisory for CVE-2017-18076

GHSA-9pr6-grf4-x2fr · Severity: high · Ecosystem: rubygems — Omniauth allows POST parameters to be stored in session

OS Trackers for CVE-2017-18076

vendor priority summary link
debian not yet assigned CVE-2017-18076 not yet assigned priority: Debian including 1 source packages (ruby-omniauth), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2017-18076
ubuntu medium CVE-2017-18076 medium priority: Ubuntu including 1 source packages (ruby-omniauth), 7 status rows across 7 suites (artful, bionic, cosmic, disco, trusty, upstream, xenial): not-affected 3, released 3, DNE 1. https://ubuntu.com/security/CVE-2017-18076

Affected software / configurations for CVE-2017-18076

Vendor Product Version Raw CPE
omniauth omniauth < 1.3.2 cpe:2.3:a:omniauth:omniauth:*:*:*:*:*:ruby:*:*
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-2017-18076

cvelogic Threat Intelligence