What is CVE-2018-12615?

CVE-2018-12615 is a medium-severity vulnerability in Phusion Passenger, classified under Incorrect Permission Assignment for Critical Resource. CVSS score: 5.3/10. Published 2018-06-21.

How severe is CVE-2018-12615?

Medium severity. CVSS v3 base score is 5.3 out of 10.

Is CVE-2018-12615 known to be exploited?

1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Vulnerability in Phusion Passenger

CVE-2018-12615

An issue was discovered in switchGroup() in agent/ExecHelper/ExecHelperMain.cpp in Phusion Passenger before 5.3.2. The set of groups (gidset) is not set correctly, leaving it up to randomness (i.e., uninitialized memory) which supplementary groups are actually being set while lowering privileges.

Published 2018-06-21 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N.

EPSS exploit prediction

EPSS: 0.012 (66.9th percentile), scored 2026-09-29.

Low probability of exploitation in the next 30 days, but still tracked. 67th percentile — 66.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.012 · newest: 0.012 · change: 0.000

Affected products

Phusion Passenger

Weakness classification (CWE)

CWE-732 — Incorrect Permission Assignment for Critical Resource

Public proof-of-concept exploits

Farrhouq/Inpt-report

References

github.com/phusion/passenger/commit/4e97fdb86d0a0141ec9a052c6e691fcd07bb45c8 (Patch, Third Party Advisory)

Frequently asked questions

What is CVE-2018-12615?: CVE-2018-12615 is a medium-severity vulnerability in Phusion Passenger, classified under Incorrect Permission Assignment for Critical Resource. CVSS score: 5.3/10. Published 2018-06-21.
How severe is CVE-2018-12615?: Medium severity. CVSS v3 base score is 5.3 out of 10.
Is CVE-2018-12615 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.