MEDIUM
CVE-2021-20712
NVD-CWE-OtherPublished: April 26, 2021· Updated: Jun 17, 2026
5.3
CVSS v3.1
Official Description
Improper access control vulnerability in NEC Aterm WG2600HS firmware Ver1.5.1 and earlier, and Aterm WX3000HP firmware Ver1.1.2 and earlier allows a device connected to the LAN side to be accessed from the WAN side due to the defect in the IPv6 firewall function.
Technical Analysis
CVE-2021-20712 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.
CVSS v3.1 Vector Breakdown
Exploitability
Attack VectorNetwork
Attack ComplexityLow
Privileges Req.None
User InteractionNone
ScopeUnchanged
Impact
ConfidentialityLow
IntegrityNone
AvailabilityNone
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Affected Vendors & Products
nec4 product(s)
aterm wg2600hs firmwareaterm wg2600hsaterm wx3000hp firmwareaterm wx3000hp
Source: NVD CPE · 4 total CPE entries
Exploit & PoC Resources
NO KNOWN EXPLOITNo public exploit confirmed at this time
Exploit-DB
Offensive Security exploit database
GitHub PoC Search
Community PoC repositories
Rapid7 / Metasploit
Metasploit module search
PacketStorm
Security advisories & exploits
NVD Detail
Official NIST entry
MITRE CVE
CVE Program entry
External links open in a new tab. Always verify in a controlled environment before use.
Official Patches & Advisories
All References (4)
→
https://jpn.nec.com/security-info/secinfo/nv21-010.htmlMitigation · Vendor Advisory
→
https://jvn.jp/en/jp/JVN29739718/index.htmlThird Party Advisory
→
https://jpn.nec.com/security-info/secinfo/nv21-010.htmlMitigation · Vendor Advisory
→
https://jvn.jp/en/jp/JVN29739718/index.htmlThird Party Advisory
Quick Facts
CVE IDCVE-2021-20712
CVSS Score5.3 / 10
SeverityMEDIUM
WeaknessNVD-CWE-Other
CISA KEVNo
Affected1 vendor(s)
PublishedApr 26, 2021
Related CVEs (NVD-CWE-Other)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2021-20712 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWATCH.COM. CVE data is provided under the NVD usage policy.