Tapo C200 v5: Missing Authentication for Critical Functionality
CVE-2026-78578 is a high-severity missing authentication for critical functionality vulnerability in Tapo C200 v5 from TP-Link, with a CVSS 4.0 base score of 7.1 out of 10. It can be exploited from the same local network by an unauthenticated attacker, without any action from a user. The record lists version V5_1.4.6 Build 260709 Rel.27675n as the first without the flaw, so updating Tapo C200 v5 to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.27% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update Tapo C200 v5 to V5_1.4.6 Build 260709 Rel.27675n or a later version.
- Update Tapo C120 v1 to V1_1.9.4 Build 260813 Rel.79754n or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| TP-Link | Tapo C200 v5 | before V5_1.4.6 Build 260709 Rel.27675n | V5_1.4.6 Build 260709 Rel.27675n |
| TP-Link | Tapo C120 v1 | before V1_1.9.4 Build 260813 Rel.79754n | V1_1.9.4 Build 260813 Rel.79754n |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- AdjacentThe attacker must be on the same local network segment.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Attack requirements
- NoneThe attack does not depend on a particular deployment or configuration.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Confidentiality (vulnerable system)
- NoneNo loss of confidentiality on the vulnerable system.
- Integrity (vulnerable system)
- NoneNo loss of integrity on the vulnerable system.
- Availability (vulnerable system)
- HighSerious loss of availability on the vulnerable system.
- Confidentiality (other systems)
- NoneNo loss of confidentiality on systems beyond the vulnerable one.
- Integrity (other systems)
- NoneNo loss of integrity on systems beyond the vulnerable one.
- Availability (other systems)
- NoneNo loss of availability on systems beyond the vulnerable one.
Vector: CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X. Scored by CNA.
Official description
Tapo C120 v1 and C200 v5 do not enforce authentication for do method HTTPS onboarding connect actions after initial setup. An unauthenticated adjacent attacker can submit unauthorized wireless configuration parameters, causing the camera to attempt connection to a different network. Successful exploitation disconnects the camera from its intended wireless network, making it unreachable on its management address, resulting in a denial-of-service condition.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Missing Authentication for Critical Functionality
The product does not perform any authentication for functionality that requires a provable user identity or consumes a significant amount of resources.
How developers prevent this class of flaw
- For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.
- Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, consider using libraries with authentication capabilities such as OpenSSL or the ESAPI Authenticator.
- When storing data in the cloud (e.g., S3 buckets, Azure blobs, Google Cloud Storage, etc.), use the provider's controls to require strong authentication for users who should be allowed to access the data.
More Missing Authentication for Critical Functionality vulnerabilities (CWE-306)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
References
Patches and release notes
Other references
Other vulnerabilities in Tapo C200 v5
- 7.1 High severity
- 8.7 High severity
- 8.8 High severity
Recent Missing Authentication for Critical Functionality vulnerabilities
- 7.1 High severity
- 7.5 High severity
- 8.8 High severity
- 7.5 High severity
- 9.8 Critical severity
- 7.1 High severity
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