CVE-2018-11627

Exp

Sinatra before 2.0.2 has XSS via the 400 Bad Request page that occurs upon a params parser exception.

Published: 2018-05-31 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2018-11627 is rated High Exploit Risk (60.4/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 0.40%). 1 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

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

Public exploit references (Exploit-DB) for CVE-2018-11627

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2018-11627

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 2025-11-21 0.32% 0.40% +0.07%
2 2025-11-18 0.40% 0.32% -0.07%
3 2025-06-06 — 0.40% —

Full EPSS history (12 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2018-11627

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.1 3.0 MEDIUM
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/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:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 2.8 2.7 [email protected]
4.3 2.0 MEDIUM
AV:N/AC:M/Au:N/C:N/I:P/A:N Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:N)
No availability impact.
 8.6 2.9 [email protected]

Weakness enumeration for CVE-2018-11627

GitHub Security Advisory for CVE-2018-11627

GHSA-mq35-wqvf-r23c · Severity: medium · Ecosystem: rubygems — Sinatra Cross-site Scripting vulnerability

OS Trackers for CVE-2018-11627

vendor priority summary link
debian unimportant CVE-2018-11627 unimportant priority: Debian including 1 source packages (ruby-sinatra), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2018-11627
redhat medium — https://access.redhat.com/security/cve/CVE-2018-11627
suse medium — https://www.suse.com/security/cve/CVE-2018-11627/
ubuntu medium CVE-2018-11627 medium priority: Ubuntu including 1 source packages (ruby-sinatra), 13 status rows across 13 suites (artful, bionic, cosmic, disco, eoan, focal, groovy, hirsute, impish, jammy, trusty, upstream, xenial): ignored 5, released 5, not-affected 2, DNE 1. https://ubuntu.com/security/CVE-2018-11627

Affected software / configurations for CVE-2018-11627

Vendor Product Version Raw CPE
sinatrarb sinatra < 2.0.2 cpe:2.3:a:sinatrarb:sinatra:*:*:*:*:*:*:*:*
redhat cloudforms 4.6 cpe:2.3:a:redhat:cloudforms:4.6:*:*:*:*:*:*:*
redhat cloudforms 4.7 cpe:2.3:a:redhat:cloudforms:4.7:*:*:*:*:*:*:*

References for CVE-2018-11627

cvelogic Threat Intelligence