CVE-2020-37164Public exploit

Local application crash via oversized license name

Published Feb 6, 2026 · Updated Feb 6, 2026

Buffer overflow in AbsoluteTelnet 11.12 allows local users to crash the application by pasting an oversized name into the license field. The license-entry dialog processes a 2,500-character license-name payload without checking its size before a buffer copy. Access to the running Windows desktop and interaction with Help > Enter License Key are required; the reported consequence is termination of that client process.

CVSS severity6.7
Medium
EPSS probability0.23%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Buffer overflow in AbsoluteTelnet 11.12 allows local users to crash the application by pasting an oversized name into the license field. The license-entry dialog processes a 2,500-character license-name payload without checking its size before a buffer copy. Access to the running Windows desktop and interaction with Help > Enter License Key are required; the reported consequence is termination of that client process.

The record

CVE
CVE-2020-37164
Published
Feb 6, 2026
Updated
Feb 6, 2026
Vendor
Celestial Software
Product
AbsoluteTelnet
Classifications
CWE-120
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 6, 2026CVE publishedPublication date reported by the CVE source.
  2. Feb 6, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=11.12

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Celestial Software · AbsoluteTelnetversion=11.12

Published CVSS scores

6.2VulnCheckCVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
6.7VulnCheckCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
5.5NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-120Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')

Public exploit references

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

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo