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CVE Record

CVE-2017-18206: In utils.c in zsh before 5.4, symlink expansion had a buffer overflow.

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

UnknownCVSS not scoredNot KEV-listedUpdated
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Glexia's TakeAutomated analysisunknown

Security readout for executives and security teams

Plain-English summary

CVE-2017-18206 is a buffer overflow in zsh symlink expansion before version 5.4. zsh is a command shell commonly installed on Unix-like systems. The bundle does not provide CVSS, impact details, or exploitation evidence, so urgency should be driven by whether zsh is installed and unpatched.

Executive priority

Treat this as routine but real patch-management work unless local exposure shows unsupported or broadly deployed zsh. There is no source-backed evidence of active exploitation in the provided bundle.

Technical view

The CVE describes a buffer overflow in utils.c during symlink expansion in zsh before 5.4. Multiple Linux vendor advisories reference security updates. The source bundle does not specify attack prerequisites, affected distributions, exploitability, or whether code execution is possible.

Likely exposure

Exposure is most likely on systems with zsh installed at a vulnerable upstream version or an unpatched vendor package. Distribution backports may report versions below 5.4 while still containing fixes, so validate against vendor advisories.

Exploitation context

The provided sources do not claim active exploitation, and the CVE is not listed as KEV in the bundle. Public evidence here is limited to the vulnerability description, upstream code reference, and vendor security advisories.

Researcher notes

Key missing details are CVSS, CWE classification, precise impact, and attack prerequisites. The upstream reference should be used only to understand the fix lineage, while remediation decisions should follow distribution advisories and package status.

Mitigation direction

  • Update zsh using the operating system vendor's supported security packages.
  • If building from source, use zsh 5.4 or later unless vendor guidance says otherwise.
  • Prioritize internet-facing administration hosts, developer workstations, and shared Unix servers.
  • Check Ubuntu, Gentoo, Red Hat, and Debian advisories for backported fixes.
  • Retire unsupported systems that cannot receive vendor zsh security updates.

Validation and detection

  • Inventory systems with zsh installed and record package versions.
  • Map installed packages to vendor advisory fixed builds, not only upstream version numbers.
  • Confirm security updates were applied successfully after patching.
  • Review configuration management for systems pinning old zsh packages.
  • Document exceptions where zsh remains installed but cannot be updated.
Prepared
Confidence
medium
Sources
8

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.

ATT&CK lookup starting points

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CVE-2017-18206 mapping review

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Vulnerability profileCVE Program record
Severity
Unknown
CVSS
Not scored
Known Exploited
No
Published
Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

0CVSS vectors
0Timeline events
0ADP providers
7Source links

CVSS and timeline data

No CVSS vectors or timeline events were available in the normalized CVE source material.

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
n/an/an/aListed
Weakness

CWE details

No CWE listed

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.