DrayTek VigorSwitch G2540xs setget.cgi Interface pass null pointer dereference

Summaryinfo

A vulnerability identified as critical has been detected in DrayTek VigorSwitch G2540xs, VigorSwitch P2540xs, VigorSwitch FX2120, VigorSwitch G2282x, VigorSwitch P2282x, VigorSwitch Q2300x, VigorSwitch PQ2300xb, VigorSwitch G2542x, VigorSwitch P2542x, VigorSwitch P2542xh, VigorSwitch PX2060, VigorSwitch G1280, VigorSwitch P1280, VigorSwitch P1281x, VigorSwitch G1282, VigorSwitch P1282, VigorSwitch G2121, VigorSwitch P2121, VigorSwitch PQ2121x, VigorSwitch Q2121x, VigorSwitch G2280x, VigorSwitch P2280x, VigorSwitch Q2200x, VigorSwitch PQ2200xb, VigorSwitch G2100, VigorSwitch P2100, VigorSwitch G2540x and VigorSwitch P2540x. The impacted element is an unknown function of the file setget.cgi of the component setget.cgi Interface. This manipulation of the argument pass causes null pointer dereference. This vulnerability appears as CVE-2026-71922. The attack may be initiated remotely. There is no available exploit.

Detailsinfo

A vulnerability has been found in DrayTek VigorSwitch G2540xs, VigorSwitch P2540xs, VigorSwitch FX2120, VigorSwitch G2282x, VigorSwitch P2282x, VigorSwitch Q2300x, VigorSwitch PQ2300xb, VigorSwitch G2542x, VigorSwitch P2542x, VigorSwitch P2542xh, VigorSwitch PX2060, VigorSwitch G1280, VigorSwitch P1280, VigorSwitch P1281x, VigorSwitch G1282, VigorSwitch P1282, VigorSwitch G2121, VigorSwitch P2121, VigorSwitch PQ2121x, VigorSwitch Q2121x, VigorSwitch G2280x, VigorSwitch P2280x, VigorSwitch Q2200x, VigorSwitch PQ2200xb, VigorSwitch G2100, VigorSwitch P2100, VigorSwitch G2540x and VigorSwitch P2540x and classified as critical. Affected by this vulnerability is some unknown functionality of the file setget.cgi of the component setget.cgi Interface. The manipulation of the argument pass with an unknown input leads to a null pointer dereference vulnerability. The CWE definition for the vulnerability is CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. As an impact it is known to affect availability. The summary by CVE is:

Multiple DrayTek VigorSwitch models contain a pre-authentication null pointer dereference vulnerability in the setget.cgi interface. The vulnerability is caused by missing validation when the pass field is absent. A remote attacker can trigger this vulnerability via a crafted request to crash the service and cause a denial of service.

The advisory is shared at draytek.com. This vulnerability is known as CVE-2026-71922 since 08/08/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details are known, but no exploit is available.

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

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

• Router Operating System

Vendor

• DrayTek

Name

• VigorSwitch FX2120
• VigorSwitch G1280
• VigorSwitch G1282
• VigorSwitch G2100
• VigorSwitch G2121
• VigorSwitch G2280x
• VigorSwitch G2282x
• VigorSwitch G2540x
• VigorSwitch G2540xs
• VigorSwitch G2542x
• VigorSwitch P1280
• VigorSwitch P1281x
• VigorSwitch P1282
• VigorSwitch P2100
• VigorSwitch P2121
• VigorSwitch P2280x
• VigorSwitch P2282x
• VigorSwitch P2540x
• VigorSwitch P2540xs
• VigorSwitch P2542x
• VigorSwitch P2542xh
• VigorSwitch PQ2121x
• VigorSwitch PQ2200xb
• VigorSwitch PQ2300xb
• VigorSwitch PX2060
• VigorSwitch Q2121x
• VigorSwitch Q2200x
• VigorSwitch Q2300x

License

• commercial

CPE 2.3info

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CPE 2.2info

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Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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