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TI-2018-09527 Aliases CVE-2018-13259GHSA-8vj4-q4ww-8jf3

Improper input validation in zsh before 5.6

Priority MEDIUM 47CWE-20Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 8 fixed, 1 without a fix

Attack profile from CVSS 3.0 · NVD. Fix status from CNA and Red Hat.

Summary

An issue was discovered in zsh before 5.6. Shebang lines exceeding 64 characters were truncated, potentially leading to an execve call to a program name that is a substring of the intended one.

Why it matters now

EPSS 0.02723 86th percentileScored 2026-11-07
Fix Partial Red Hat: 1 advisoryRed Hat: 8 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
—zsh before 5.6zsh before 5.6—No fix listedCNA
  • zsh before 5.6 Vendor— Affected zsh before 5.6 Fixed in — No fix listed CNA

CPE configurations NVD · 4

CPEVersionsRoleVendor
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:a:zsh:zsh:*:*:*:*:*:*:*:*before 5.6Vulnerablezsh
  • 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:a:zsh:zsh:*:*:*:*:*:*:*:* Versions before 5.6 Vulnerable ·zsh

Remediation

Red Hat 1 advisory

  • RHSA-2019:2017 Released 2019-08-06 · Red Hat rating Moderate
    zsh security and bug fix update
    • Red Hat Enterprise Linux Client (v. 7) zsh-5.0.2-33.el7
    • Red Hat Enterprise Linux Client Optional (v. 7) zsh-html-5.0.2-33.el7
    • Red Hat Enterprise Linux ComputeNode (v. 7) zsh-5.0.2-33.el7
    • Red Hat Enterprise Linux ComputeNode Optional (v. 7) zsh-html-5.0.2-33.el7
    • Red Hat Enterprise Linux Server (v. 7) zsh-5.0.2-33.el7
    • Red Hat Enterprise Linux Server Optional (v. 7) zsh-html-5.0.2-33.el7
    • Red Hat Enterprise Linux Workstation (v. 7) zsh-5.0.2-33.el7
    • Red Hat Enterprise Linux Workstation Optional (v. 7) zsh-html-5.0.2-33.el7

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Advisory ·

    zsh before 5.6 — GLSA-201903-02

    2 records Highest priority Priority MEDIUM 2 MEDIUM

    Other records, highest priority first

    • TI-2018-00459 Improper input validation in zsh before 5.6Priority MEDIUM 47
    Show all 2 records → Advisory →

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 Enterprise Linux Client (v. 7)Fixed RHSA-2019:2017
Red Hat Enterprise Linux Client Optional (v. 7)Fixed RHSA-2019:2017
Red Hat Enterprise Linux ComputeNode (v. 7)Fixed RHSA-2019:2017
Red Hat Enterprise Linux ComputeNode Optional (v. 7)Fixed RHSA-2019:2017
Red Hat Enterprise Linux Server (v. 7)Fixed RHSA-2019:2017
Red Hat Enterprise Linux Server Optional (v. 7)Fixed RHSA-2019:2017
Red Hat Enterprise Linux Workstation (v. 7)Fixed RHSA-2019:2017
Red Hat Enterprise Linux Workstation Optional (v. 7)Fixed RHSA-2019:2017
Not affected: 2 products
  • Red Hat Enterprise Linux 5
  • Red Hat Enterprise Linux 8

Timeline

  1. 2026-10-02 Threatist record created from CVE-2018-13259
  2. 2026-10-03 Alias added: GHSA-8vj4-q4ww-8jf3

References

Patch 2

Advisory 4

Other 1

Sources

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