Resource Allocation Without LimitsWeakness · CWE-770

CVE-2021-47875

CRITICAL · 9.8 CVSS v3.1 Published 2026-01-21
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
100/100
Remediation priority · Urgent
Public exploit Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
GeoGebra CAS Calculator 6.0.631.0 contains a denial of service vulnerability that allows attackers to crash the application by generating a large buffer overflow. Attackers can create a payload with 8000 repeated characters and paste it into the calculator's input field to trigger an application crash.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · moderate confidence

GeoGebra CAS Calculator 6.0.631.0 contains a buffer overflow vulnerability in its input validation handling. An attacker can trigger a denial of service by pasting a crafted payload of approximately 8000 repeated characters into the calculator's input field, causing the application to crash.

MitigationImplement strict input length validation and bounds checking on all user input fields to reject oversized payloads before processing. Users should update to a patched version if available.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Verify GeoGebra CAS Calculator is installed
    Check for the application in standard installation paths (e.g., C:\Program Files\GeoGebra CAS Calculator or C:\Program Files (x86)\GeoGebra CAS Calculator), or search for 'GeoGebra CAS Calculator' in your system's application list.
    Affected if The application is found on the system
  2. Determine the installed version
    Right-click the GeoGebra CAS Calculator executable, select Properties, and check the 'File version' or 'Product version' field in the Details tab. Alternatively, open the app and go to Help > About.
    Affected if The version is 6.0.631.0 or earlier (the specific vulnerable version listed is 6.0.631.0)
  3. Confirm CAS Calculator input functionality is accessible
    Open GeoGebra CAS Calculator and locate the main input field (the CAS input area where mathematical expressions are entered for computation).
    Affected if The CAS input field is present and functional, allowing user-provided text input
  4. Test input length susceptibility (optional validation)
    In the CAS input field, attempt to paste or enter a string of approximately 8000 repeated characters (e.g., 'A' repeated 8000 times). Observe if the application crashes or becomes unresponsive.
    Affected if The application crashes or hangs when 8000+ characters are entered in the input field, confirming the buffer overflow is triggerable

A user is affected if GeoGebra CAS Calculator version 6.0.631.0 (or any earlier version) is installed and the CAS input field accepts large character strings without crashing.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Implement strict input length validation and bounds checking on all user input fields to reject oversized payloads before processing. Users should update to a patched version if available.

Have this fixed Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing3.0 h
  • Review / QA2.0 h
11.0 hours of engineering $1,930
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Scan for this in your stack

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dbcve dependency scanner

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2021-47875 in production — separate from our analysis above.

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
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