CVE-2006-3694: Multiple unspecified vulnerabilities in Ruby before 1.8.5 allow remote attackers to bypass "safe level" checks

This month

MEDIUM 6.4DOWNGRADE

CVE-2006-3694 is a medium-severity flaw (CVSS 6.4) affecting ruby. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

Multiple unspecified vulnerabilities in Ruby before 1.8.5 allow remote attackers to bypass "safe level" checks via unspecified vectors involving (1) the alias function and (2) "directory operations".

Why this priority

EPSS top 7%: very likely to be exploited

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

Risk facts

CVSS score	6.4 (Medium)
EPSS exploit chance	5.8% (top 7%)
CISA exploited list	No
Published	2006-07-21
Last modified	2026-06-16

Publisher (CNA): MITRE · Vendor: yukihiro matsumoto

Last updated 2026-06-16 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2006-07-21 14:03 UTCPublished CVE record published
2026-06-16 22:27 UTCUpdated Record last modified

yukihiro matsumoto ruby DOWNGRADE

Affected: 1.8.2 · 1.8.3 · 1.8.4

Fixed in: no fixed release known

Safe to downgrade to: a release before 1.8.2

1. Check installed version

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

2. No fixed release: DOWNGRADE to a release before 1.8.2 (Debian / Ubuntu)

apt-cache madison ruby sudo apt install ruby=<VERSION_BEFORE_1.8.2> sudo apt-mark hold ruby

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

dnf --showduplicates list ruby sudo dnf downgrade ruby-<VERSION_BEFORE_1.8.2> sudo dnf versionlock add ruby

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-2006-3694?

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

Is CVE-2006-3694 being exploited?

CVE-2006-3694 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-2006-3694 affect?

CVE-2006-3694 affects ruby. Severity is medium (CVSS 6.4). Multiple unspecified vulnerabilities in Ruby before 1.8.5 allow remote attackers to bypass "safe level" checks via unspecified vectors involving (1) the alias function and (2) "directory operations".

How urgent is CVE-2006-3694?

Priority 46/100. EPSS top 7%: very likely to be exploited

Software pages

Ruby vulnerabilities

Related CVEs

CVE-2026-97229 CRITICAL 10.0 EXPLOITED UPGRADE UPGRADE GitLab Community Edition and Enterprise Edition Integer Overflow or Wraparound Vulnerability
CVE-2026-46727 HIGH 8.1 UPGRADE An issue was discovered in Ruby 4 before 4.0.5
CVE-2023-28756 MEDIUM 5.3 UPGRADE DOWNGRADE A ReDoS issue was discovered in the Time component through 0.2.1 in Ruby through 3.2.1
CVE-2022-28739 HIGH 7.5 UPGRADE MITIGATE There is a buffer over-read in Ruby before 2.6.10, 2.7.x before 2.7.6, 3.x before 3.0.4, and 3.1.x before 3.1.
CVE-2022-28738 CRITICAL 9.8 UPGRADE A double free was found in the Regexp compiler in Ruby 3.x before 3.0.4 and 3.1.x before 3.1.2

References

← Back to latest CVEs