Broken Access Control Leading to Cross-Device Token Issuance in Tapo Cloud MQTT Proxy
Affects Tapo Cloud Service across the full listed version range, which starts at 0. No vendor rating or fixed version is listed. CVSS scores it 8.3 (high).
Written by anthropic/claude-haiku-5.5 from the sources below. Verify against them.
- Exploited
- No known exploitation
- Fix
- No fix listed
- Who is exposed
- Not reported
Do first: Workaround: The checked facts give no workaround or mitigation. No vendor fix is listed, so the bug remains open according to these facts.
- Exploitation?/40Exploitation: unknown (data gap). No CISA SSVC exploitation rating yet
- Exposure17/25No login or user action needed, reachable over the network without a login · Data gap: Advisories don't say whether default setups are affected
- Reach?/20Reach: unknown (data gap). No tracked technology or package matched
- Severity8.3/10CVSS 8.3
- No patch5/5No patch listed yet
What would change the score
- Would score about 75 if added to CISA KEV
- Would score about 70 if CISA's SSVC rates exploitation active
- Would score about 35 if advisories confirm default setups are exposed
CVE-2026-105821 is not in CISA's Known Exploited Vulnerabilities (KEV) catalog. No public exploit code is tracked. It is rated CVSS 8.3 (high) and affects Tapo Cloud Service; no fixed version is listed yet.
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- Published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- A 0-100 score for how much a CVE matters across the industry: exploitation, exposure, how widely the software is used, severity and whether a fix exists.What do these mean? →
- 30/100 · provisional
- How many real-world setups can hit the bug, from the vendor's advisory and CISA data. It does not know your setup.What do these mean? →
- Unclear
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
The Tapo Cloud MQTT broker, which Tapo smart home devices and the Tapo app rely on for cloud communication, is affected by this vulnerability. An attacker who owns a Tapo device could use it to obtain access tokens for another user's device and upload fake content to that user's Tapo Cloud storage, potentially presenting it as a genuine event and exposing internal service information or disrupting service availability.
Read the original description
The Tapo Cloud MQTT broker contains a broken access control vulnerability in a proxy topic used by authenticated Tapo devices to request service tokens. The broker does not verify that the device ID supplied in a proxy request belongs to the authenticated device. An attacker who owns a Tapo device and knows another device's ID may obtain a device token scoped to the target device and use it to upload attacker-controlled content to the target user's Tapo Cloud storage. The content may then be presented in the Tapo app as a legitimate event. Successful exploitation may allow an attacker to upload attacker-controlled content that is presented to a target user as a legitimate Tapo event, retrieve internal service information through crafted proxy requests, or abuse Tapo Cloud outbound request capability in activity that could affect service availability.
What to do
Workaround: The checked facts give no workaround or mitigation. No vendor fix is listed, so the bug remains open according to these facts.
Timeline
- CVE published
- First seen by cve.now
Affected versions
- TP-Link Systems Inc. Tapo Cloud Service
All versions
Evidence 1
- Advisory
Corrections
None so far.
Something wrong on this page? Report an error. Every fix is listed here.
Questions about CVE-2026-105821
Is CVE-2026-105821 being exploited?
It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked.Source: cve.now feed data
What does this mean?
The Tapo Cloud MQTT broker does not check that the device ID in a proxy request belongs to the authenticated device. An attacker who owns a Tapo device and knows another device's ID can obtain a token scoped to that other device and upload attacker-controlled content to the target user's Tapo Cloud storage, where it may appear in the Tapo app as a legitimate event.Source: tp-link.com
Which versions are affected by CVE-2026-105821?
Tapo Cloud Service: all versions.Source: cve.now feed data
Am I affected, and how do I check?
The listed range starts at version 0, so all Tapo Cloud Service versions in the checked facts are listed as affected. The setup involves owning a Tapo device and knowing the target device's ID. The checked facts do not name a version command or setting to check.Source: tp-link.com
How do I fix CVE-2026-105821?
The checked facts list no fixed version, so no upgrade target can be named. Check the vendor advisory for a fix before relying on any update.Source: tp-link.com
What if there's no patch?
The checked facts give no workaround or mitigation. No vendor fix is listed, so the bug remains open according to these facts.Source: tp-link.com