CVE-2021-34863

Severity: high (CVSS 8.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-10-25 · updated 2026-06-17
Weakness: CWE-121

Description

This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of D-Link DAP-2020 1.01rc001 routers. Authentication is not required to exploit this vulnerability. The specific flaw exists within the handling of the var:page parameter provided to the webproc endpoint. The issue results from the lack of proper validation of the length of user-supplied data prior to copying it to a fixed-length stack-based buffer. An attacker can leverage this vulnerability to execute code in the context of root. Was ZDI-CAN-13271.

Affected products

D-Link DAP-2020: through 1.01

References

https://supportannouncement.us.dlink.com/announcement/publication.aspx?name=SAP10201
https://www.zerodayinitiative.com/advisories/ZDI-21-979/
https://supportannouncement.us.dlink.com/announcement/publication.aspx?name=SAP10201
https://www.zerodayinitiative.com/advisories/ZDI-21-979/

Get alerted when CVE-2021-34863 or the next vulnerability affects your stack