Cyber Posture

CVE-2021-47877

HighPublic PoC

Published: 21 January 2026

Published
21 January 2026
Modified
15 April 2026
KEV Added
Patch
CVSS Score 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS Score 0.0004 12.7th percentile
Risk Priority 15 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-47877 is a high-severity Allocation of Resources Without Limits or Throttling (CWE-770) vulnerability in Geogebra (inferred from references). Its CVSS base score is 7.5 (High).

Operationally, ranked at the 12.7th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

Threat & Defense Details

Likely Mitigating ControlsAI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-770

This control implements explicit throttling on session allocation, addressing the weakness of allocating resources without limits.

addresses: CWE-770

Plan testing exercises resource allocation limits and throttling during simulated failures, directly addressing weaknesses that allow unbounded resource use.

addresses: CWE-770

Contingency plan updates ensure recovery strategies address unbounded resource allocation, making it harder for attackers to exploit lack of throttling to cause prolonged outages.

addresses: CWE-770

Provides continuity when unbounded resource allocation at the primary site leads to exhaustion and downtime.

addresses: CWE-770

Alternate services allow operations to continue when primary allocation of resources lacks limits or throttling.

addresses: CWE-770

Explicit planning of security-related actions requires defining limits, windows, and resource allocations, making allocation without throttling far less likely.

addresses: CWE-770

Measures of performance include tracking allocation behavior and throttling effectiveness, reducing the window for resource exhaustion attacks.

addresses: CWE-770

Imposes an inactivity-based limit on network resource allocation, throttling the number of concurrently held connections.

NVD Description

GeoGebra Graphing Calculator 6.0.631.0 contains a denial of service vulnerability that allows attackers to crash the application by inputting an oversized buffer. Attackers can generate a payload of 8000 repeated characters to overwhelm the input field and cause the application…

more

to become unresponsive.

Deeper analysisAI

CVE-2021-47877 is a denial of service vulnerability in GeoGebra Graphing Calculator version 6.0.631.0. The flaw stems from inadequate handling of oversized input buffers, where attackers can input a payload of 8000 repeated characters into an input field, overwhelming the application and causing it to crash or become unresponsive. It is classified under CWE-770 (Allocation of Resources Without Limits or Throttling) with a CVSS v3.1 base score of 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H).

The vulnerability can be exploited remotely by any unauthenticated attacker with low attack complexity and no user interaction required. Exploitation involves crafting and delivering the oversized character payload to the affected input field, resulting in high-impact denial of service that renders the graphing calculator application unusable.

Advisories and a proof-of-concept exploit are documented in references such as Exploit-DB (https://www.exploit-db.com/exploits/49653) and Vulncheck (https://www.vulncheck.com/advisories/geogebra-graphing-calculator-denial-of-service), with the official GeoGebra site at https://www.geogebra.org. No specific patch or mitigation details are outlined in the provided information.

Details

CWE(s)

Affected Products

Geogebra
inferred from references and description; NVD did not file a CPE for this CVE

CVEs Like This One

CVE-2025-8099Shared CWE-770
CVE-2021-47895Shared CWE-770
CVE-2020-37085Shared CWE-770
CVE-2026-20103Shared CWE-770
CVE-2024-12537Shared CWE-770
CVE-2026-33256Shared CWE-770
CVE-2026-26313Shared CWE-770
CVE-2026-31283Shared CWE-770
CVE-2026-35401Shared CWE-770
CVE-2025-1059Shared CWE-770

References