Fiche vulnérabilité
CVE-2021-27137 : faille exploitée dd-wrt dd-wrt (CVSS 8.1)
Description
An issue was discovered in router/upnp/src/ssdp.c in DD-WRT before 45724. An unsafe strcpy in the UPnP handling functionality allows an unauthenticated remote attacker to send a request that would overflow an internal fixed buffer. Exploitation requires the DD-WRT user to enable UPnP (which is off by default, and only listens on internal interfaces by default). This occurs in ssdp_msearch (reachable by an M-SEARCH request).
En bref
- Sévérité
- Élevée (CVSS 8.1)
- Vecteur CVSS
- CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
- Exploitation active
- Oui, inscrite au catalogue CISA KEV
- Publication
- 16 juil. 2026
- Dernière mise à jour
- 22 juil. 2026
Produits concernés
- dd-wrt dd-wrt
Correctif et mesures
Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.