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TI-2017-13391 Aliases CVE-2017-18206GHSA-vpqc-mgq5-m5xg

In utils.c in zsh before 5.4, symlink expansion had a buffer overflow.

Priority MEDIUM 48CWE-119Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 18 fixed, 1 without a fix

Attack profile from CVSS 3.0 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-119 and the CVSS impact.

Summary

In utils.c in zsh before 5.4, symlink expansion had a buffer overflow.

Why it matters now

EPSS 0.03114 87th percentileScored 2026-11-07
Fix Partial Red Hat: 2 advisoriesRed Hat: 18 fixed, 1 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 · 4

CPEVersionsRoleVendor
cpe:2.3:a:zsh:zsh:*:*:*:*:*:*:*:*before 5.4Vulnerablezsh
cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:*14.04VulnerableCanonical
cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:*16.04VulnerableCanonical
cpe:2.3:o:canonical:ubuntu_linux:17.10:*:*:*:*:*:*:*17.10VulnerableCanonical
  • cpe:2.3:a:zsh:zsh:*:*:*:*:*:*:*:* Versions before 5.4 Vulnerable ·zsh
  • cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:* Versions 14.04 Vulnerable ·Canonical
  • cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:* Versions 16.04 Vulnerable ·Canonical
  • cpe:2.3:o:canonical:ubuntu_linux:17.10:*:*:*:*:*:*:* Versions 17.10 Vulnerable ·Canonical

Remediation

Red Hat 2 advisories

  • RHSA-2018:3073 Released 2018-10-30 · Red Hat rating Moderate
    zsh security and bug fix update
    • Red Hat Enterprise Linux Client (v. 7) zsh-5.0.2-31.el7
    • Red Hat Enterprise Linux Client Optional (v. 7) zsh-html-5.0.2-31.el7
    • Red Hat Enterprise Linux ComputeNode (v. 7) zsh-5.0.2-31.el7
    • Red Hat Enterprise Linux ComputeNode Optional (v. 7) zsh-html-5.0.2-31.el7
    • Red Hat Enterprise Linux Server (v. 7) zsh-5.0.2-31.el7
    • Red Hat Enterprise Linux Server Optional (v. 7) zsh-html-5.0.2-31.el7
    • Red Hat Enterprise Linux Workstation (v. 7) zsh-5.0.2-31.el7
    • Red Hat Enterprise Linux Workstation Optional (v. 7) zsh-html-5.0.2-31.el7
    • Red Hat Enterprise Linux for ARM and IBM Power LE (POWER9) Server (v. 7) zsh-5.0.2-31.el7
    • Red Hat Enterprise Linux for ARM and IBM Power LE (POWER9) Server Optional (v. 7) zsh-html-5.0.2-31.el7
  • RHSA-2018:1932 Released 2018-06-19 · Red Hat rating Moderate
    zsh security update
    • Red Hat Enterprise Linux Desktop (v. 6) zsh-4.3.11-8.el6
    • Red Hat Enterprise Linux Desktop Optional (v. 6) zsh-html-4.3.11-8.el6
    • Red Hat Enterprise Linux HPC Node (v. 6) zsh-4.3.11-8.el6
    • Red Hat Enterprise Linux HPC Node Optional (v. 6) zsh-html-4.3.11-8.el6
    • Red Hat Enterprise Linux Server (v. 6) zsh-4.3.11-8.el6
    • Red Hat Enterprise Linux Server Optional (v. 6) zsh-html-4.3.11-8.el6
    • Red Hat Enterprise Linux Workstation (v. 6) zsh-4.3.11-8.el6
    • Red Hat Enterprise Linux Workstation Optional (v. 6) zsh-html-4.3.11-8.el6

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux 5AffectedNo fix planned: Will not fix
Red Hat Enterprise Linux Client (v. 7)Fixed RHSA-2018:3073
Red Hat Enterprise Linux Client Optional (v. 7)Fixed RHSA-2018:3073
Red Hat Enterprise Linux ComputeNode (v. 7)Fixed RHSA-2018:3073
Red Hat Enterprise Linux ComputeNode Optional (v. 7)Fixed RHSA-2018:3073
Red Hat Enterprise Linux Desktop (v. 6)Fixed RHSA-2018:1932
Red Hat Enterprise Linux Desktop Optional (v. 6)Fixed RHSA-2018:1932
Red Hat Enterprise Linux HPC Node (v. 6)Fixed RHSA-2018:1932
Red Hat Enterprise Linux HPC Node Optional (v. 6)Fixed RHSA-2018:1932
Red Hat Enterprise Linux Server (v. 6)Fixed RHSA-2018:1932
Red Hat Enterprise Linux Server (v. 7)Fixed RHSA-2018:3073
Red Hat Enterprise Linux Server Optional (v. 6)Fixed RHSA-2018:1932
Red Hat Enterprise Linux Server Optional (v. 7)Fixed RHSA-2018:3073
Red Hat Enterprise Linux Workstation (v. 6)Fixed RHSA-2018:1932
Red Hat Enterprise Linux Workstation (v. 7)Fixed RHSA-2018:3073
Red Hat Enterprise Linux Workstation Optional (v. 6)Fixed RHSA-2018:1932
Red Hat Enterprise Linux Workstation Optional (v. 7)Fixed RHSA-2018:3073
Red Hat Enterprise Linux for ARM and IBM Power LE (POWER9) Server (v. 7)Fixed RHSA-2018:3073
Red Hat Enterprise Linux for ARM and IBM Power LE (POWER9) Server Optional (v. 7)Fixed RHSA-2018:3073
Not affected: 1 product
  • Red Hat Enterprise Linux 8

Timeline

  1. 2026-10-02 Threatist record created from CVE-2017-18206
  2. 2026-10-03 Alias added: GHSA-vpqc-mgq5-m5xg

References

Patch 1

Advisory 4

Other 1

Sources

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