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TI-2021-02393 Aliases CVE-2021-3429GHSA-jj89-4799-j2qv

sensitive data exposure in cloud-init logs

Priority LOW 24CWE-532Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Information disclosure
Confidentiality · integrity · availability
High · None · None
Fix status
Partial Red Hat: 3 fixed, 2 without a fix

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-532.

Summary

When instructing cloud-init to set a random password for a new user account, versions before 21.2 would write that password to the world-readable log file /var/log/cloud-init-output.log. This could allow a local user to log in as another user.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00219 12th percentileScored 2026-11-07
Fix Partial cloud-init (Canonical Ltd.): 21.2Red Hat: 3 advisoriesRed Hat: 3 fixed, 2 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
Canonicalcloud-initbefore 21.221.2Patch availableCNA
  • cloud-init VendorCanonical Affected before 21.2 Fixed in 21.2 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:canonical:cloud-init:*:*:*:*:*:*:*:*before 21.2VulnerableCanonical
  • cpe:2.3:a:canonical:cloud-init:*:*:*:*:*:*:*:* Versions before 21.2 Vulnerable ·Canonical

Remediation

  • Fix · CNA cloud-init (Canonical Ltd.) Fixed in 21.2

Red Hat 3 advisories

  • RHSA-2021:3371 Released 2021-08-31 · Red Hat rating Moderate
    cloud-init security update
    • Red Hat Enterprise Linux AppStream EUS (v. 8.2) cloud-init-18.5-12.el8_2.10
  • RHSA-2021:3177 Released 2021-08-17 · Red Hat rating Moderate
    cloud-init security update
    • Red Hat Enterprise Linux AppStream EUS (v. 8.1) cloud-init-18.5-7.el8_1.6
  • RHSA-2021:3081 Released 2021-08-10 · Red Hat rating Moderate
    cloud-init security update
    • Red Hat Enterprise Linux AppStream (v. 8) cloud-init-20.3-10.el8_4.5

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 6AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 7AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux AppStream (v. 8)Fixed RHSA-2021:3081
Red Hat Enterprise Linux AppStream EUS (v. 8.1)Fixed RHSA-2021:3177
Red Hat Enterprise Linux AppStream EUS (v. 8.2)Fixed RHSA-2021:3371
Not affected: 1 product
  • Red Hat Enterprise Linux 9

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-3429
  2. 2026-10-03 Alias added: GHSA-jj89-4799-j2qv

References

Patch 1

  • TI-2012-05357 Improper privilege management in cloud-init CVSS 3.1HIGH 8.8
  • TI-2024-05723 Improper authentication in Canonical cloud-init CVSS 3.1HIGH 8.8
  • TI-2018-07709 The default cloud-init configuration, in cloud-init 0.6.2 and newer, included… CVSS 3.1HIGH 7.1
  • TI-2024-10733 Incorrect permission assignment in Canonical cloud-init CVSS 3.1MEDIUM 5.9
  • TI-2020-06920 In cloud-init through 19.4, rand_user_password in cloudinit/config/cc_set_passwords.py… CVSS 3.1MEDIUM 5.5
  • TI-2020-06919 cloud-init through 19.4 relies on Mersenne Twister for a random password, which makes it… CVSS 3.1MEDIUM 5.5
See all 8 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences