Tenda AC20 up to 16.03.08.12 /goform/WifiGuestSet shareSpeed buffer overflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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8.4$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as critical, was found in Tenda AC20 up to 16.03.08.12. Affected by this vulnerability is an unknown functionality of the file /goform/WifiGuestSet. The manipulation of the argument shareSpeed results in buffer overflow. This vulnerability is reported as CVE-2025-8939. The attack can be launched remotely. Moreover, an exploit is present.

Detailsinfo

A vulnerability was found in Tenda AC20 up to 16.03.08.12. It has been classified as critical. Affected is some unknown functionality of the file /goform/WifiGuestSet. The manipulation of the argument shareSpeed with an unknown input leads to a buffer overflow vulnerability. CWE is classifying the issue as CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow. This is going to have an impact on confidentiality, integrity, and availability.

The advisory is available at github.com. This vulnerability is traded as CVE-2025-8939. The exploitability is told to be easy. It is possible to launch the attack remotely. Technical details and a public exploit are known.

The exploit is shared for download at github.com. It is declared as proof-of-concept.

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

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Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 8.8
VulDB Meta Temp Score: 8.4

VulDB Base Score: 8.8
VulDB Temp Score: 8.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 8.8
CNA Vector: 🔒

CVSSv2info

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

Exploitinginfo

Class: Buffer overflow
CWE: CWE-120 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Access: Public
Status: Proof-of-Concept
Download: 🔒

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

08/13/2025 Advisory disclosed
08/13/2025 +0 days VulDB entry created
08/15/2025 +2 days VulDB entry last update

Sourcesinfo

Vendor: tenda.com.cn

Advisory: github.com
Status: Not defined

CVE: CVE-2025-8939 (🔒)
GCVE (CVE): GCVE-0-2025-8939
GCVE (VulDB): GCVE-100-319902
scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 08/13/2025 14:06
Updated: 08/15/2025 17:10
Changes: 08/13/2025 14:06 (56), 08/14/2025 13:16 (31), 08/15/2025 17:10 (1)
Complete: 🔍
Submitter: QMSSDXN
Cache ID: 216::103

Submitinfo

Accepted

  • Submit #631829: Tenda AC20 ≤ V16.03.08.12 (latest version) Buffer Overflow (by QMSSDXN)

Duplicate

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