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TI-2017-13390 Aliases CVE-2017-18205GHSA-r2ph-r5g8-q5vv

In builtin.c in zsh before 5.4, when sh compatibility mode is used, there is a NULL…

Priority LOW 39CWE-476Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
High
Impact type
Denial of service
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 10 fixed, 2 without a fix

Attack profile from CVSS 3.0 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-476.

Summary

In builtin.c in zsh before 5.4, when sh compatibility mode is used, there is a NULL pointer dereference during processing of the cd command with no argument if HOME is not set.

Why it matters now

EPSS 0.02043 81st percentileScored 2026-11-07
Fix Partial Red Hat: 1 advisoryRed Hat: 10 fixed, 2 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 · 1

CPEVersionsRoleVendor
cpe:2.3:a:zsh_project:zsh:*:*:*:*:*:*:*:*before 5.4VulnerableZsh Project
  • cpe:2.3:a:zsh_project:zsh:*:*:*:*:*:*:*:* Versions before 5.4 Vulnerable ·Zsh Project

Remediation

Red Hat 1 advisory

  • 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

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 6AffectedNo 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 Server (v. 7)Fixed RHSA-2018:3073
Red Hat Enterprise Linux Server Optional (v. 7)Fixed RHSA-2018:3073
Red Hat Enterprise Linux Workstation (v. 7)Fixed RHSA-2018:3073
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-2017-18205
  2. 2026-10-03 Alias added: GHSA-r2ph-r5g8-q5vv

References

Patch 1

Advisory 3

  • TI-2014-08228 In utils.c in zsh before 5.0.6, there is a buffer overflow when scanning very long directory paths for symbolic links. CVSS 3.0CRITICAL 9.8
  • TI-2014-08226 zsh before 5.0.7 allows evaluation of the initial values of integer variables imported… CVSS 3.0HIGH 7.8

Sources

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