Read the docs
TI-2020-04265 Aliases CVE-2020-5209

NetHack command line parsing of options starting with -de and -i is subject to a buffer overflow

Priority LOW 36CWE-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
Fixed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-120 and the CVSS impact.

Summary

In NetHack before 3.6.5, unknown options starting with -de and -i can cause a buffer overflow resulting in a crash or remote code execution/privilege escalation. This vulnerability affects systems that have NetHack installed suid/sgid and shared systems that allow users to influence command line options. Users should upgrade to NetHack 3.6.5.

Why it matters now

EPSS 0.00803 56th percentileScored 2026-11-07
Fix Fixed NetHack (NetHack): 3.6.5

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
NetHackNetHackbefore 3.6.53.6.5Patch availableCNA
  • NetHack VendorNetHack Affected before 3.6.5 Fixed in 3.6.5 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:nethack:nethack:*:*:*:*:*:*:*:*before 3.6.5VulnerableNetHack
  • cpe:2.3:a:nethack:nethack:*:*:*:*:*:*:*:* Versions before 3.6.5 Vulnerable ·NetHack

Remediation

  • Fix · CNA NetHack (NetHack) Fixed in 3.6.5

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-10-02 Threatist record created from CVE-2020-5209

References

Patch 1

Advisory 1

  • TI-2019-14352 NetHack 3.6.x before 3.6.4 is prone to a buffer overflow vulnerability when reading very… CVSS 3.1CRITICAL 9.8
  • TI-2020-04270 NetHack error recovery after syntax error in configuration file is subject to a buffer overflow CVSS 3.1CRITICAL 9.8
  • TI-2020-04269 NetHack SYMBOL configuration file option is subject to a buffer overflow CVSS 3.1CRITICAL 9.8
  • TI-2020-04268 NetHack MENUCOLOR configuration file option is subject to a buffer overflow CVSS 3.1CRITICAL 9.8
  • TI-2020-04267 NetHack AUTOCOMPLETE configuration file option is subject to a buffer overflow CVSS 3.1CRITICAL 9.8
  • TI-2020-04309 Privilege escalation in NetHack CVSS 3.1CRITICAL 9.8
See all 10 →

Sources

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