CVE-2021-20123
Exploited in the wild. In CISA KEV since 2024‑09‑03. A vendor fix is available.
What to do
The vendor has published a fix. Version details are below where the sources state them.
What it is
From the CVE record
A local file inclusion vulnerability exists in Draytek VigorConnect 1.6.0-B3 in the file download functionality of the DownloadFileServlet endpoint. An unauthenticated attacker could leverage this vulnerability to download arbitrary files from the underlying operating system with root privileges.
In plain language
No plain-language summary for this CVE yet.
Exploitation
Where each signal puts this CVE on the scale from published to confirmed exploited.
- CISA KEV
Listed as exploited in the wild since 2024-09-03.
US federal agencies must remediate by 2024-09-24.
Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
- Public exploits
1 source with a proof of concept or module.
Exploit links, PoCs and Metasploit modules after sign-in- EPSS
90% chance of exploitation activity in the next 30 days, which ranks it in the 99th percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
The patch came 123 days before any public exploit.
- EPSS band changehigh → criticalepss band change
- OpenVAS check added
- EPSS band changecritical → high
- Public exploit / PoCsource: othernuclei check added
- Patch availablerecord updated
- Added to CISA KEV
Affected products
And 2 more affected products. See all after sign-in
Technical detail
CVSS 3.1 vector
Open in the CVSS calculatorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Scored 7.5 by NVD.
How it is reached
- Attack Vector NetworkExploitable remotely over the network without any special conditions
- Attack Complexity LowNo special conditions — the attack can be reliably reproduced
- Privileges Required NoneNo authentication required — anyone can exploit this
- User Interaction NoneNo user interaction needed — fully automated exploitation
Scope
- Scope UnchangedImpact is limited to the vulnerable component itself
Impact if exploited
- Confidentiality HighTotal information disclosure — all data in the component is compromised
- Integrity NoneNo integrity impact
- Availability NoneNo availability impact
Weaknesses
ATT&CK techniques
Mapped from the weaknesses above (CWE to ATT&CK), not observed in attacks.
Sources
References in the record
- nvd.nist.gov/vuln/detail/CVE-2021-20123&
- vuldb.com/?id.184384&
- cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-20123&
And 4 more references. See all after sign-in
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We'll flag the next CVE, public exploit or patch for VigorConnect, not every advisory. This one: actively exploited.
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