CVE-2026-66902

CRITICAL
INFO Priority: 0.07 BB Relevance: 80/100
Published: 2026-08-04 Modified: 2026-10-24 First seen: 2026-10-29 Status: active

Attack Surface

Network Low Complexity No Auth No Interaction Conf. Impact Integ. Impact

CVSS Vector Breakdown

AV: Network
AC: Low
PR: None
UI: None
S: Unchanged
C: High
I: High
A: High

Description

Google::Auth versions before 0.06 for Perl run a command named in an external_account credentials JSON via an ungated system call. The Pluggable subclass reads credential_source.executable.command from the credentials JSON and runs it as `system($command)`, a single argument call that passes the whole string to /bin/sh -c. The executable's environment_variables map from the same JSON is copied into %ENV first. No opt-in gate guards the call. make_creds selects the Pluggable subclass whenever credential_source.executable is present, so the path is reached from the standard Application Default Credentials flow, including a "type": "external_account" configuration read from the file named by GOOGLE_APPLICATION_CREDENTIALS. Configurations without credential_source.executable do not select this subclass and do not reach the call. Any caller that builds credentials from a configuration it does not fully control runs the embedded command with the privileges of the application process.

Weakness Classification (2)

Bug Bounty Relevance

80 / 100
✓ Network accessible
✓ No authentication
✓ Low complexity
✓ No user interaction

CVSS Score

9.8 / 10.0 v3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS — Exploitation Probability

0.70%
Raw Score 0.007020
Percentile 53.2%
Date 2026-10-29

EPSS Trend

2026-10-29
0.00702
2026-10-28
0.00702

Intelligence Sources

nvd ref →