CVE-2020-5212

Code execution via oversized MENUCOLOR value

Published Jan 28, 2020 · Updated Aug 4, 2024

Buffer overflow in NetHack before 3.6.5 allows local users to crash the game or execute code via an extremely long MENUCOLOR value. The add_menu_coloring() configuration parser does not reject an oversized MENUCOLOR value before it overruns a buffer. Exploitation requires a setuid or setgid installation, or a shared host that lets users supply their own configuration files; successful code execution inherits the game's elevated context.

CVSS severity5.0
Medium
EPSS probability1.07%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Buffer overflow in NetHack before 3.6.5 allows local users to crash the game or execute code via an extremely long MENUCOLOR value. The add_menu_coloring() configuration parser does not reject an oversized MENUCOLOR value before it overruns a buffer. Exploitation requires a setuid or setgid installation, or a shared host that lets users supply their own configuration files; successful code execution inherits the game's elevated context.

The record

CVE
CVE-2020-5212
Published
Jan 28, 2020
Updated
Aug 4, 2024
Vendor
NetHack
Product
NetHack
Classifications
CWE-120, T1068
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Jan 28, 2020CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 3.6.5

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

NetHack · NetHackversion=< 3.6.5

Published CVSS scores

5.0CanonicalCVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:C/C:L/I:L/A:L

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-120Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')
T1068Exploitation for Privilege Escalation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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