CVE-2019-13589: The paranoid2 gem 1.1.6 for Ruby, as distributed on RubyGems.org, included a code-execution backdoor inserted

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CRITICAL 9.8REMOTEDOWNGRADE

CVE-2019-13589 is a critical-severity flaw (CVSS 9.8) affecting paranoid2. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

The paranoid2 gem 1.1.6 for Ruby, as distributed on RubyGems.org, included a code-execution backdoor inserted by a third party. The current version, without this backdoor, is 1.1.5.

Why this priority

Critical severity
EPSS top 9%: very likely to be exploited
Public exploit reference
Remotely exploitable, no login, no user action

No fix is published yet: follow the downgrade or mitigation steps.

Risk facts

CVSS score	9.8 (Critical)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	4.3% (top 9%)
CISA exploited list	No
Weakness	CWE-829
Published	2019-07-14
Last modified	2026-06-17

Publisher (CNA): MITRE · Vendor: anjlab

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2019-07-14 16:15 UTCPublished CVE record published
2026-06-17 02:17 UTCUpdated Record last modified

anjlab paranoid2 DOWNGRADE

Affected: 1.1.6

Fixed in: no fixed release known

Safe to downgrade to: a release before 1.1.6

1. Check installed version

apt-cache policy paranoid2 || rpm -q paranoid2 || paranoid2 --version

2. No fixed release: DOWNGRADE to a release before 1.1.6 (Debian / Ubuntu)

apt-cache madison paranoid2 sudo apt install paranoid2=<VERSION_BEFORE_1.1.6> sudo apt-mark hold paranoid2

2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list paranoid2 sudo dnf downgrade paranoid2-<VERSION_BEFORE_1.1.6> sudo dnf versionlock add paranoid2

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2019-13589?

paranoid2: downgrade or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2019-13589 being exploited?

CVE-2019-13589 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2019-13589 affect?

CVE-2019-13589 affects paranoid2. Severity is critical (CVSS 9.8). The paranoid2 gem 1.1.6 for Ruby, as distributed on RubyGems.org, included a code-execution backdoor inserted by a third party. The current version, without this backdoor, is 1.1.5.

How urgent is CVE-2019-13589?

Priority 67/100. Critical severity; EPSS top 9%: very likely to be exploited; Public exploit reference; Remotely exploitable, no login, no user action

Software pages

Ruby vulnerabilities

References

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