DrayTek VigorAP 903 setLan lanVlanId0/lanIp/lanNetmask buffer overflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
8.2$0-$5k1.27

Summaryinfo

A vulnerability was found in DrayTek VigorAP 918R, VigorAP 960C, VigorAP 1060C, VigorAP 906, VigorAP 912C and VigorAP 903 and classified as very critical. Affected is the function setLan. The manipulation of the argument lanVlanId0/lanIp/lanNetmask results in buffer overflow. This vulnerability is cataloged as CVE-2026-71911. The attack may be launched remotely. There is no exploit available.

Detailsinfo

A vulnerability, which was classified as very critical, was found in DrayTek VigorAP 918R, VigorAP 960C, VigorAP 1060C, VigorAP 906, VigorAP 912C and VigorAP 903. Affected is the function setLan. The manipulation of the argument lanVlanId0/lanIp/lanNetmask 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. CVE summarizes:

Multiple DrayTek VigorAP models contain a buffer overflow vulnerability in the setLan function. The vulnerability is caused by missing length checks during memory copy operations involving the lanVlanId0, lanIp, and lanNetmask fields. A remote attacker can trigger this vulnerability via crafted input, causing a denial of service or potentially executing arbitrary commands. Exploitation requires valid administrative credentials for the device's web management interface.

The advisory is available at draytek.com. This vulnerability is traded as CVE-2026-71911 since 08/08/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. Additional levels of successful authentication are needed for exploitation. Technical details are known, but there is no available exploit. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 08/24/2026).

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

License

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: 8.2
VulDB Meta Temp Score: 8.2

VulDB Base Score: 9.1
VulDB Temp Score: 9.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.2
CNA Vector (VulnCheck): 🔒

CVSSv2info

AVACAuCIA
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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: 🔒
Status: Not defined
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

08/08/2026 CVE reserved
08/24/2026 +16 days Advisory disclosed
08/24/2026 +0 days VulDB entry created
08/24/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: draytek.com
Status: Not defined

CVE: CVE-2026-71911 (🔒)
GCVE (CVE): GCVE-0-2026-71911
GCVE (VulDB): GCVE-100-394734

Entryinfo

Created: 08/24/2026 19:34
Changes: 08/24/2026 19:34 (74)
Complete: 🔍
Cache ID: 216::103

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