QEMU QXL Display Device Emulation cursor_alloc heap-based overflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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8.1$5k-$25k0.00

Summaryinfo

A vulnerability described as critical has been identified in QEMU. This affects the function cursor_alloc of the component QXL Display Device Emulation. Such manipulation leads to heap-based overflow. This vulnerability is listed as CVE-2021-4206. There is no available exploit.

Detailsinfo

A vulnerability was found in QEMU (Virtualization Software) (unknown version). It has been rated as critical. Affected by this issue is the function cursor_alloc of the component QXL Display Device Emulation. The manipulation with an unknown input leads to a heap-based overflow vulnerability. Using CWE to declare the problem leads to CWE-122. A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc(). Impacted is confidentiality, integrity, and availability.

The weakness was presented 04/30/2022. The advisory is shared for download at starlabs.sg. This vulnerability is handled as CVE-2021-4206 since 01/13/2022. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $5k-$25k (estimation calculated on 03/21/2025).

The vulnerability scanner Nessus provides a plugin with the ID 209571 (Oracle Linux 8 : virt:kvm_utils3 (ELSA-2024-12792)), which helps to determine the existence of the flaw in a target environment.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at Tenable (209571). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

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Name

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.1
VulDB Meta Temp Score: 8.1

VulDB Base Score: 8.0
VulDB Temp Score: 8.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 8.2
NVD Vector: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Heap-based overflow
CWE: CWE-122 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 209571
Nessus Name: Oracle Linux 8 : virt:kvm_utils3 (ELSA-2024-12792)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍

Timelineinfo

01/13/2022 🔍
04/30/2022 +106 days 🔍
04/30/2022 +0 days 🔍
03/21/2025 +1056 days 🔍

Sourcesinfo

Product: qemu.org

Advisory: starlabs.sg
Status: Not defined

CVE: CVE-2021-4206 (🔍)
GCVE (CVE): GCVE-0-2021-4206
GCVE (VulDB): GCVE-100-198728

Entryinfo

Created: 04/30/2022 08:10
Updated: 03/21/2025 20:24
Changes: 04/30/2022 08:10 (37), 05/04/2022 11:49 (1), 10/25/2024 06:28 (16), 03/21/2025 20:24 (19)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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