Denial of Service Vulnerability in GeoGebra Classic by GeoGebra
CVE-2021-47876

6.7MEDIUM

Key Information:

Vendor

Geogebra

Status
Geogebra Classic
Vendor
CVE Published:
21 January 2026

Badges

👾 Exploit Exists🟡 Public PoC

What is CVE-2021-47876?

GeoGebra Classic 5.0.631.0-d is susceptible to a denial of service vulnerability due to its handling of oversized input in the application. An attacker can exploit this vulnerability by pasting an excessively large buffer, consisting of 800,000 repeated characters, into the 'Entrada:' input field. This action can result in the application crashing, thereby disrupting the user experience and potentially affecting service availability.

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Affected Version(s)

GeoGebra Classic 5.0.631.0

Exploit Proof of Concept (PoC)

PoC code is written by security researchers to demonstrate the vulnerability can be exploited. PoC code is also a key component for weaponization which could lead to ransomware.

CVE-2021-47876 - Proof of Concept

References

https://www.exploit-db.com/exploits/49654
exploit
https://www.geogebra.org
product
https://www.vulncheck.com/advisories/geogebra-classic-d-d...
third-party-advisory

CVSS V4

Score:
6.7
Severity:
MEDIUM
Confidentiality:
None
Integrity:
None
Availability:
High
Attack Vector:
Local
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
Unknown

Timeline

  • 🟡

    Public PoC available

  • 👾

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

Credit

Brian Rodriguez
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