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PatchSiren cyber security CVE debrief

CVE-2026-9460 Edimax CVE debrief

A stack-based buffer overflow vulnerability exists in the Edimax EW-7438RPn wireless range extender firmware version 1.31. The vulnerability is located in the `formAccept` function within the `/goform/formAccept` endpoint, where improper handling of the `submit-url` argument allows remote attackers to trigger memory corruption. The CVSS 4.0 vector indicates network attack vector with low attack complexity, low privileges required, and no user interaction needed, resulting in high impacts to confidentiality, integrity, and availability. The exploit has been publicly disclosed, and the vendor was reportedly contacted without response. The vulnerability status in NVD is currently marked as 'Deferred'.

Vendor
Edimax
Product
EW-7438RPn
CVSS
HIGH 7.4
CISA KEV
Not listed in stored evidence
Original CVE published
2026-05-25
Original CVE updated
2026-05-26
Advisory published
2026-05-25
Advisory updated
2026-05-26

Who should care

Organizations deploying Edimax EW-7438RPn range extenders in production environments, particularly those with management interfaces exposed to internal networks or improperly segmented from untrusted access. Security teams responsible for IoT device inventory and patch management should prioritize identification of affected firmware versions.

Technical summary

The vulnerability stems from insufficient bounds checking in the `formAccept` function when processing the `submit-url` HTTP parameter. A remote attacker with low privileges can send a crafted request to `/goform/formAccept` with an oversized `submit-url` value, causing a stack-based buffer overflow. This memory corruption can be leveraged to achieve arbitrary code execution on the affected device. The attack requires network access to the device's web management interface but does not require user interaction.

Defensive priority

HIGH

Recommended defensive actions

  • Segment or restrict network access to Edimax EW-7438RPn management interfaces, particularly the /goform/formAccept endpoint
  • Monitor for anomalous HTTP requests to /goform/formAccept containing oversized or malformed submit-url parameters
  • Apply firmware updates from Edimax when available; consider discontinuing use if no patch is forthcoming
  • Deploy web application firewall rules to filter suspicious input to the formAccept endpoint
  • Review logs for indicators of compromise if devices are internet-exposed

Evidence notes

Vulnerability identified through Vuldb CNA submission. Technical details and proof-of-concept published via GitHub repository. NVD status shows 'Deferred' indicating pending analysis or vendor coordination.

Official resources

Public disclosure occurred on 2026-05-25 with exploit availability confirmed. Vendor was contacted prior to disclosure but did not respond.