CVE-2021-27137

Katalog CVE

CVSS 8.1 · High KEV · sudah dieksploitasi EPSS 4,0%

Kerentanan Stack-based Buffer Overflow pada dd-wrt. Skor CVSS 3.1 8.1 (High) menurut mitre.org. Masuk katalog KEV CISA pada 21 Juli 2026, artinya sudah terbukti dieksploitasi.

Deskripsi (NVD)

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).

Rincian

Terbit di NVD

16 Juli 2026

Terakhir diubah

22 Juli 2026

Status NVD

Analyzed

CVSS 3.1

8.1 (High), sumber mitre.org
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H · uraikan di kalkulator

Jenis kelemahan (CWE)

CWE-121: Stack-based Buffer Overflow

EPSS (30 hari)

4,0% peluang dieksploitasi; lebih tinggi dari 90,3% CVE lain

Known Exploited Vulnerabilities (CISA)

Nama

DD-WRT Stack-Based Buffer Overflow Vulnerability

Masuk KEV

21 Juli 2026

Tenggat CISA

24 Juli 2026 (untuk instansi federal AS)

Ransomware

Belum tercatat

Tindakan wajib

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.

Produk dan versi terdampak

> Data dari konfigurasi CPE di NVD.

Referensi dan perbaikan

• https://svn.dd-wrt.com/changeset/45724 patch
• https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-27137 pemerintah AS
• https://securityaffairs.com/193290/uncategorized/iot-botnet-c0xmo-adds-competitor-killing-capability.html exploit · advisory pihak ketiga
• https://ssd-disclosure.com/ssd-advisory-dd-wrt-upnp-buffer-overflow/ exploit · advisory pihak ketiga
• https://www.bleepingcomputer.com/news/security/c0xmo-botnet-spreads-via-dd-wrt-router-flaw-kills-rival-malware... exploit · advisory pihak ketiga
• https://www.fortinet.com/blog/threat-research/inside-cross-platform-propagation-of-new-gafgyt-variant-c0xmo exploit