CVE-2018-12026

During the spawning of a malicious Passenger-managed application, SpawningKit in Phusion Passenger 5.3.x before 5.3.2 allows such applications to replace key files or directories in the spawning communication directory with symlinks. This then could result in arbitrary reads and writes, which in turn can result in information disclosure and privilege escalation.

Published: 2018-06-17 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2018-12026 is rated High Risk (66.4/100): CVSS Critical severity, with medium exploitation likelihood (EPSS 1.12%). High exploitation likelihood—assess exposure and prioritize 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-2018-12026

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 2026-01-01 1.18% 1.12% -0.06%
2 2025-03-30 1.60% 1.18% -0.42%
3 2025-03-29 — 1.60% —

Full EPSS history (7 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2018-12026

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.8 3.0 CRITICAL
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/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:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 5.9 [email protected]
7.5 2.0 HIGH
AV:N/AC:L/Au:N/C:P/I:P/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:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
 10.0 6.4 [email protected]

Weakness enumeration for CVE-2018-12026

GitHub Security Advisory for CVE-2018-12026

GHSA-7cv3-gvmc-8mq5 · Severity: critical · Ecosystem: rubygems — Phusion Passenger SpawningKit Contains Arbitrary Read/Write Vulnerability

OS Trackers for CVE-2018-12026

vendor priority summary link
debian unimportant CVE-2018-12026 unimportant priority: Debian including 1 source packages (passenger), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2018-12026
gentoo normal CVE-2018-12026: 1 GLSA(s) (201807-02), 1 atom(s) (www-apache/passenger); latest impact normal. https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2018-12026
redhat high — https://access.redhat.com/security/cve/CVE-2018-12026
ubuntu medium CVE-2018-12026 medium priority: Ubuntu including 2 source packages (passenger, ruby-passenger), 26 status rows across 13 suites (artful, bionic, cosmic, disco, eoan, focal, groovy, hirsute, impish, jammy, trusty, upstream, xenial): DNE 13, ignored 6, not-affected 5, needs-triage 1, released 1. https://ubuntu.com/security/CVE-2018-12026

Affected software / configurations for CVE-2018-12026

Vendor Product Version Raw CPE
phusion passenger >= 5.3.0, < 5.3.2 cpe:2.3:a:phusion:passenger:*:*:*:*:*:*:*:*

References for CVE-2018-12026

URL Tags
https://blog.phusion.nl/passenger-5-3-2 Mitigation Vendor Advisory
https://security.gentoo.org/glsa/201807-02 Third Party Advisory
cvelogic Threat Intelligence