CVE-2017-18206

CRITICALNVD 9.89.8—
EchelonGraph scoreMEDIUM confidence

Score 9.8 from GitHub Security Advisory (severity: CRITICAL) published 2022-05-13. NVD baseline CVSS 9.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
9.8EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 3%CVSS: 9.8Exploit: None knownExposed: 0

A fix is available — apply it.

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

CVSS v3
9.8
EG Score
9.8(medium)
EG Risk
50(Track)
EG Risk 50/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity98% × 45%
Exploitation3% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
3%
EPSS %ILE
87%
KEV
Not listed

Published

February 27, 2018

Last Modified

November 21, 2024

Advisory Details (5)

Auto-updated Sep 5, 2026
Patch available. Sources: redhat.
generic

Zsh: Multiple vulnerabilities (GLSA 201805-10) — Gentoo security

https://security.gentoo.org/glsa/201805-10
generic Patch Available

[SECURITY] [DLA 2470-1] zsh security update

https://lists.debian.org/debian-lts-announce/2020/12/msg00000.html
redhat Patch Available

Affected: Red Hat Enterprise Linux 7.

https://access.redhat.com/errata/RHSA-2018:3073
redhat Patch Available

Affected: Red Hat Enterprise Linux 6.

https://access.redhat.com/errata/RHSA-2018:1932
generic

zsh / Code / Commit [c7a9cf]

https://sourceforge.net/p/zsh/code/ci/c7a9cf465dd620ef48d586026944d9bd7a0d5d6d

Vendor Advisories for CVE-2017-18206(2)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Patch Availability(3)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntuzsh (5.2-5ubuntu1.1) @ artful2026-05-28ubuntu
redhatzsh-0:5.0.2-31.el72018-10-30redhat
redhatzsh-0:4.3.11-8.el62018-06-19redhat

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(6 across 6 ecosystems)
Debian:11(1)
PackageVulnerable rangeFixed inDependents
zsh—5.4.1-1—
Debian:12(1)
PackageVulnerable rangeFixed inDependents
zsh—5.4.1-1—
Debian:13(1)
PackageVulnerable rangeFixed inDependents
zsh—5.4.1-1—
Debian:14(1)
PackageVulnerable rangeFixed inDependents
zsh—5.4.1-1—
Debian:7(1)
PackageVulnerable rangeFixed inDependents
zsh4.3.17-14.3.17-1+deb7u1—
Debian:9(1)
PackageVulnerable rangeFixed inDependents
zsh5.3.1-45.3.1-4+deb9u1—

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Additional Vendor Advisories

(1)

Vendors that published advisories for this CVE beyond the curated set above. Broader coverage but minimal per-row detail — click through for the original advisory.

Data Freshness Timeline

(refreshed 6× in last 7d / 21× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

Showing the most recent 100 of 125 total refreshes for this CVE.

  1. 2026-09-07 15:56 UTCEPSS rescore
  2. 2026-09-06 13:43 UTCEPSS rescore
  3. 2026-09-05 15:23 UTCEPSS rescore
  4. 2026-09-04 13:56 UTCEPSS rescore
  5. 2026-09-02 14:07 UTCEPSS rescore
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  7. 2026-09-01 03:31 UTCEPSS rescore
  8. 2026-08-30 19:13 UTCEPSS rescore
  9. 2026-08-27 14:21 UTCEPSS rescore
  10. 2026-08-26 14:41 UTCEPSS rescore
  11. 2026-08-25 13:44 UTCEPSS rescore
  12. 2026-08-22 22:07 UTCOSV refresh
  13. 2026-08-21 23:44 UTCEPSS rescore
  14. 2026-08-20 22:51 UTCEPSS rescore
  15. 2026-08-19 16:59 UTCEPSS rescore
  16. 2026-08-18 13:43 UTCEPSS rescore
  17. 2026-08-17 13:42 UTCEPSS rescore
  18. 2026-08-16 14:51 UTCEPSS rescore
  19. 2026-08-16 02:10 UTCEPSS rescore
  20. 2026-08-15 01:26 UTCEPSS rescore
  21. 2026-08-12 13:46 UTCEPSS rescore
  22. 2026-08-09 13:42 UTCEPSS rescore
  23. 2026-08-07 16:22 UTCEPSS rescore
  24. 2026-08-07 01:04 UTCOSV refresh
  25. 2026-08-06 13:42 UTCEPSS rescore
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  1. 2026-08-05 19:12 UTCEPSS rescore
  2. 2026-08-04 15:05 UTCEPSS rescore
  3. 2026-08-02 02:23 UTCEPSS rescore
  4. 2026-08-01 04:11 UTCEPSS rescore
  5. 2026-07-30 16:24 UTCEPSS rescore
  6. 2026-07-30 01:26 UTCEPSS rescore
  7. 2026-07-28 15:32 UTCEPSS rescore
  8. 2026-07-26 14:51 UTCEPSS rescore
  9. 2026-07-23 14:15 UTCEPSS rescore
  10. 2026-07-23 01:28 UTCEG score recompute
  11. 2026-07-22 22:07 UTCEG score recompute
  12. 2026-07-22 14:04 UTCEPSS rescore
  13. 2026-07-22 14:04 UTCEPSS rescore
  14. 2026-07-21 16:48 UTCOSV refresh
  15. 2026-07-21 15:21 UTCEPSS rescore
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  17. 2026-07-20 17:04 UTCEPSS rescore
  18. 2026-07-19 14:28 UTCEPSS rescore
  19. 2026-07-19 14:28 UTCEPSS rescore
  20. 2026-07-19 02:26 UTCEPSS rescore
  21. 2026-07-19 02:26 UTCEPSS rescore
  22. 2026-07-18 10:00 UTCEPSS rescore
  23. 2026-07-16 16:59 UTCEPSS rescore
  24. 2026-07-16 16:59 UTCEPSS rescore
  25. 2026-07-15 16:54 UTCEPSS rescore
  26. 2026-07-15 01:56 UTCEPSS rescore
  27. 2026-07-15 01:56 UTCEPSS rescore
  28. 2026-07-13 22:26 UTCEPSS rescore
  29. 2026-07-12 05:43 UTCEPSS rescore
  30. 2026-07-11 08:24 UTCEPSS rescore
  31. 2026-07-09 19:06 UTCEPSS rescore
  32. 2026-07-08 15:10 UTCEPSS rescore
  33. 2026-07-07 13:42 UTCEPSS rescore
  34. 2026-07-06 16:24 UTCEPSS rescore
  35. 2026-07-06 16:24 UTCEPSS rescore
  36. 2026-07-06 02:20 UTCEPSS rescore
  37. 2026-07-06 02:20 UTCEPSS rescore
  38. 2026-07-05 02:27 UTCEPSS rescore
  39. 2026-07-04 12:26 UTCOSV refresh
  40. 2026-07-04 06:28 UTCEPSS rescore
  41. 2026-07-02 16:54 UTCEPSS rescore
  42. 2026-07-01 15:02 UTCEPSS rescore
  43. 2026-06-30 23:19 UTCEPSS rescore
  44. 2026-06-30 23:19 UTCEPSS rescore
  45. 2026-06-29 14:03 UTCEPSS rescore
  46. 2026-06-28 04:53 UTCEPSS rescore
  47. 2026-06-27 03:06 UTCEPSS rescore
  48. 2026-06-27 03:05 UTCEPSS rescore
  49. 2026-06-25 13:47 UTCEPSS rescore
  50. 2026-06-24 14:02 UTCEPSS rescore
  51. 2026-06-24 14:02 UTCEPSS rescore
  52. 2026-06-22 14:23 UTCEPSS rescore
  53. 2026-06-22 14:23 UTCEPSS rescore
  54. 2026-06-21 14:54 UTCEPSS rescore
  55. 2026-06-21 14:54 UTCEPSS rescore
  56. 2026-06-21 01:57 UTCEPSS rescore
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  58. 2026-06-19 19:23 UTCEPSS rescore
  59. 2026-06-19 19:23 UTCEPSS rescore
  60. 2026-06-18 17:50 UTCEPSS rescore
  61. 2026-06-17 17:50 UTCEPSS rescore
  62. 2026-06-16 17:50 UTCEPSS rescore
  63. 2026-06-16 17:50 UTCEPSS rescore
  64. 2026-06-16 00:13 UTCOSV refresh
  65. 2026-06-15 17:45 UTCEPSS rescore
  66. 2026-06-14 23:14 UTCEPSS rescore
  67. 2026-06-13 22:57 UTCEPSS rescore
  68. 2026-06-12 23:09 UTCEPSS rescore
  69. 2026-06-10 22:15 UTCEPSS rescore
  70. 2026-06-10 13:19 UTCEPSS rescore
  71. 2026-06-08 14:14 UTCEPSS rescore
  72. 2026-06-08 14:14 UTCEPSS rescore
  73. 2026-06-07 15:22 UTCEPSS rescore
  74. 2026-06-07 15:22 UTCEPSS rescore
  75. 2026-06-06 13:45 UTCEPSS rescore

Related CVEs(same vendor + same CWE)

Frequently asked(5)

What is CVE-2017-18206?
CVE-2017-18206 is a critical vulnerability published on February 27, 2018. In utils.c in zsh before 5.4, symlink expansion had a buffer overflow.
When was CVE-2017-18206 disclosed?
CVE-2017-18206 was first published in the National Vulnerability Database on February 27, 2018, with the most recent update on November 21, 2024. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2017-18206 actively exploited?
CVE-2017-18206 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 3% probability of exploitation in the next 30 days, which ranks it in the top 13.1% of all scored CVEs.
What is the CVSS score of CVE-2017-18206?
CVE-2017-18206 has a CVSS v3 base score of 9.8 (NVD).
How do I remediate CVE-2017-18206?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2017-18206, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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