CVE-2021-21940
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedA heap-based buffer overflow vulnerability exists in the pushMuxer processRtspInfo functionality of Anker Eufy Homebase 2 2.1.6.9h. A specially-crafted network packet can lead to a heap buffer overflow. An attacker can send a malicious packet to trigger this vulnerability.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · moderate confidenceHeap-based buffer overflow in the pushMuxer component's processRtspInfo function of Anker Eufy Homebase 2 v2.1.6.9h. The vulnerability is triggered by specially-crafted network packets (likely RTSP traffic), allowing an attacker to overflow heap memory and potentially achieve remote code execution.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data= 2.1.6.9hCVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- Low
- Privileges
- None
- User interaction
- None
- Scope
- Changed
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
-
Identify the device modelLog into the Eufy Homebase 2 web interface or mobile app and confirm the device is specifically the Homebase 2 model. Check the device label or system information page for the model number.Affected if The device is not an Anker Eufy Homebase 2 unit.
-
Check the installed firmware versionIn the Eufy Security app, navigate to Homebase Settings > About > Firmware Version, or access the web interface and look under System > Version. Record the exact firmware version string.Affected if The firmware version is exactly 2.1.6.9h.
-
Confirm RTSP service is enabledCheck the Homebase 2 settings for RTSP streaming. In the Eufy Security app, go to Homebase Settings > RTSP and verify if RTSP streaming is turned ON. Alternatively, check if RTSP port (default 8554) is listening on the device.Affected if RTSP streaming is enabled and the RTSP port is open/listening on the Homebase 2.
-
Assess network exposureScan your network to determine if the Homebase 2 RTSP port (typically 8554) or RTSP-over-TCP ports are accessible from outside your local network. Use a network scanner or check port forwarding rules on your router/firewall.Affected if The RTSP service is exposed to untrusted networks or the internet.
You are affected if you have an Anker Eufy Homebase 2 running firmware version 2.1.6.9h with RTSP streaming enabled and accessible to network attackers.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
From vendor dataApply vendor firmware patch when available; until then, restrict network access to the Homebase 2 device and block external RTSP traffic at network perimeter.
- Consultation4.0 h
- Implementation16.0 h
- Testing12.0 h
- Review / QA6.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $10,496.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-21940 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2021-21940 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.
A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.
- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
- No spam, self-promotion, credentials, or personal data