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TI-2018-01019 Aliases CVE-2018-1100GHSA-hwhr-jcvf-mgf3

Buffer overflow in zsh

Priority LOW 35CWE-120Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
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 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-120 and the CVSS impact.

Summary

zsh through version 5.4.2 is vulnerable to a stack-based buffer overflow in the utils.c:checkmailpath function. A local attacker could exploit this to execute arbitrary code in the context of another user.

Why it matters now

EPSS 0.00532 45th 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
zshzshthrough 5.4.2—No fix listedCNA
  • zsh Vendorzsh Affected through 5.4.2 Fixed in — No fix listed CNA

CPE configurations NVD · 10

CPEVersionsRoleVendor
cpe:2.3:a:zsh:zsh:*:*:*:*:*:*:*:*up to 5.4.2Vulnerablezsh
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:18.04:*:*:*:lts:*:*:*18.04VulnerableCanonical
cpe:2.3:o:redhat:enterprise_linux_desktop:6.0:*:*:*:*:*:*:*6.0VulnerableRed Hat
cpe:2.3:o:redhat:enterprise_linux_desktop:7.0:*:*:*:*:*:*:*7.0VulnerableRed Hat
cpe:2.3:o:redhat:enterprise_linux_server:6.0:*:*:*:*:*:*:*6.0VulnerableRed Hat
cpe:2.3:o:redhat:enterprise_linux_server:7.0:*:*:*:*:*:*:*7.0VulnerableRed Hat
cpe:2.3:o:redhat:enterprise_linux_workstation:6.0:*:*:*:*:*:*:*6.0VulnerableRed Hat
cpe:2.3:o:redhat:enterprise_linux_workstation:7.0:*:*:*:*:*:*:*7.0VulnerableRed Hat
  • cpe:2.3:a:zsh:zsh:*:*:*:*:*:*:*:* Versions up to 5.4.2 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:18.04:*:*:*:lts:*:*:* Versions 18.04 Vulnerable ·Canonical
  • cpe:2.3:o:redhat:enterprise_linux_desktop:6.0:*:*:*:*:*:*:* Versions 6.0 Vulnerable ·Red Hat
  • cpe:2.3:o:redhat:enterprise_linux_desktop:7.0:*:*:*:*:*:*:* Versions 7.0 Vulnerable ·Red Hat
  • cpe:2.3:o:redhat:enterprise_linux_server:6.0:*:*:*:*:*:*:* Versions 6.0 Vulnerable ·Red Hat
  • cpe:2.3:o:redhat:enterprise_linux_server:7.0:*:*:*:*:*:*:* Versions 7.0 Vulnerable ·Red Hat
  • cpe:2.3:o:redhat:enterprise_linux_workstation:6.0:*:*:*:*:*:*:* Versions 6.0 Vulnerable ·Red Hat
  • cpe:2.3:o:redhat:enterprise_linux_workstation:7.0:*:*:*:*:*:*:* Versions 7.0 Vulnerable ·Red Hat

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-2018-1100
  2. 2026-10-03 Alias added: GHSA-hwhr-jcvf-mgf3

References

Patch 1

Advisory 5

Other 1

  • TI-2017-13391 In utils.c in zsh before 5.4, symlink expansion had a buffer overflow. CVSS 3.0CRITICAL 9.8
  • TI-2018-09527 Improper input validation in zsh before 5.6 CVSS 3.0CRITICAL 9.8
  • TI-2018-05456 In subst.c in zsh through 5.4.2, there is a NULL pointer dereference when using ${(PA)...} on an empty array result. CVSS 3.0CRITICAL 9.8
  • TI-2018-00459 Improper input validation in zsh before 5.6 CVSS 3.0CRITICAL 9.8
  • TI-2014-08227 In exec.c in zsh before 5.0.7, there is a buffer overflow for very long fds in the ">& fd" syntax. CVSS 3.0CRITICAL 9.8
  • TI-2016-08755 In zsh before 5.3, an off-by-one error resulted in undersized buffers that were intended to support PATH_MAX characters. CVSS 3.0CRITICAL 9.8
See all 12 →

Sources

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