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CVE-2020-3923
TONNET DVR – Broken Access Control
High8.1EPSS 1.7%
- Published
- Updated
- Reserved
- Assigned by
- twcert
Description
DVR firmware in TAT-76 and TAT-77 series of products, provided by TONNET, contain misconfigured authentication mechanism. Attackers can crack the default password and gain access to the system.
Timeline
ID reserved
By twcert
- 2 months later
· 2 months later
Published
- 5 years later
· 5 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| twcertCNA (assigner) | 3.1 | High8.1 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVDNVD · Modified | 3.1 | Critical9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 1.7% · top 23% of all CVEs (7 Nov 2026)
Loading the EPSS history…
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.1.
Weakness
- Broken Access Control
- CWE-287 (opens in a new tab)All about CWE-287 and its CVEs
Affected products
What to do
Solution: Update to ver. 20191216 in TAT-76 series Update to ver. 20200213 in TAT-77 series
References (2)
- https://tvn.twcert.org.tw/taiwanvn/TVN-201910003 (opens in a new tab)x_refsource_MISCx_transferred
- https://www.chtsecurity.com/news/4ef5eb3a-fdc3-4d78-8dd7-ec7213e2bbcf (opens in a new tab)x_refsource_MISCx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2020-3923)Record last updated .