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TI-2018-14326 Aliases CVE-2018-20217GHSA-f4hc-rvh5-8phv

A Reachable Assertion issue was discovered in the KDC in MIT Kerberos 5 (aka krb5) before…

Priority LOW 27CWE-617Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
High
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 7 fixed, 4 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-617.

Summary

A Reachable Assertion issue was discovered in the KDC in MIT Kerberos 5 (aka krb5) before 1.17. If an attacker can obtain a krbtgt ticket using an older encryption type (single-DES, triple-DES, or RC4), the attacker can crash the KDC by making an S4U2Self request.

Why it matters now

EPSS 0.01417 72nd percentileScored 2026-11-07
Fix Partial Red Hat: 7 fixed, 4 without a fix

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
——all versions—No fix listedCNA
  • — Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 3

CPEVersionsRoleVendor
cpe:2.3:a:mit:kerberos:*:*:*:*:*:*:*:*before 5-1.17Vulnerablemoos-ivp
cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*8.0VulnerableDebian
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*9.0VulnerableDebian
  • cpe:2.3:a:mit:kerberos:*:*:*:*:*:*:*:* Versions before 5-1.17 Vulnerable ·moos-ivp
  • cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:* Versions 8.0 Vulnerable ·Debian
  • cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* Versions 9.0 Vulnerable ·Debian

Remediation

No fixed version listed by the sources yet.

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: Will not fix
Red Hat JBoss Core ServicesAffectedNo fix planned: Out of support scope
Red Hat JBoss Enterprise Application Platform 6AffectedNo fix planned: Out of support scope
Red Hat JBoss Enterprise Web Server 2AffectedNo fix planned: Out of support scope
Red Hat Ansible Tower 3.4 for RHEL 7 ServerFixed—
Red Hat Enterprise Linux Client (v. 7)Fixed—
Red Hat Enterprise Linux Client Optional (v. 7)Fixed—
Red Hat Enterprise Linux ComputeNode (v. 7)Fixed—
Red Hat Enterprise Linux ComputeNode Optional (v. 7)Fixed—
Red Hat Enterprise Linux Server (v. 7)Fixed—
Red Hat Enterprise Linux Workstation (v. 7)Fixed—
Not affected: 2 products
  • Red Hat Enterprise Linux 5
  • Red Hat Enterprise Linux 8

Timeline

  1. 2026-10-02 Threatist record created from CVE-2018-20217
  2. 2026-10-03 Alias added: GHSA-f4hc-rvh5-8phv

References

Patch 2

Advisory 4

Sources

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