Buffer overflow in NETGEAR D6220
CVE-2021-27239
This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of NETGEAR R6400 and R6700 firmware version 1.0.4.98 routers. Authentication is not required to exploit this vulnerability. The specific flaw exists within the upnpd service, which listens on UDP port 1900 by default. A crafted MX header field in an SSDP message can trigger an overflow of a fixed-length stack-based buffer. An attacker can leverage this vulnerability to execute code in the context of root. Was ZDI-CAN-11851.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.007 (52.8th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 53rd percentile — 52.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.007 · newest: 0.007 · change: -0.000
Affected products
Weakness classification (CWE)
Public proof-of-concept exploits
References
- www.zerodayinitiative.com/advisories/ZDI-21-206/ (VDB Entry, Third Party Advisory)
- kb.netgear.com/000062820/Security-Advisory-for-Stack-based-Buffer-Overflow-Remo… (Vendor Advisory)
Frequently asked questions
- What is CVE-2021-27239?
- CVE-2021-27239 is a high-severity vulnerability in NETGEAR D6220, classified under Stack-based Buffer Overflow. CVSS score: 8.8/10. Published 2021-03-29.
- How severe is CVE-2021-27239?
- High severity. CVSS v3 base score is 8.8 out of 10.
- Is CVE-2021-27239 known to be exploited?
- 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.