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CVE-2021-42911

Published: Mar 29, 2022Updated: Nov 21, 2024 Sources: CVE List NVD BDUCWE-134
NVD MITRE
9.8CVSSCRITICAL
EPSS Score
3.3%
Top 13.1%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Am I actually vulnerable?1 Nuclei template available — see how to check your systems. How to verify

Description

A Format String vulnerability exists in DrayTek Vigor 2960 <= 1.5.1.3, DrayTek Vigor 3900 <= 1.5.1.3, and DrayTek Vigor 300B <= 1.5.1.3 in the mainfunction.cgi file via a crafted HTTP message containing malformed QUERY STRING, which could let a remote malicious user execute arbitrary code.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:HI:HA:H
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:HConfidentiality
High
I:HIntegrity
High
A:HAvailability
High
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Weaknesses

CWE-134

Affected Products

Vigor 2960DrayTekNetworking Infrastructure
Vigor 3900DrayTekNetworking Infrastructure
Vigor300BDrayTekNetworking Infrastructure
n/an/a
vigor2960 firmwaredraytekNetworking Infrastructure
draytekcommercialTWNetworking Infrastructureaka draytek corp.
and 2 more affected products View all →

Attack Graph

Products CVE Techniques Tactics

Click technique nodes to view MITRE ATT&CK details. Scroll to zoom, drag to pan.

Exploitability

Official Patch Available

MITRE ATT&CK

1 technique
Execution
View detailed technique mapping

References

https://www.forescout.com/blog/draytek-routers-exploited-in-massive-ransomware-campaign-analysis-and-recommendations/&#13;
forescout.com
https://gist.github.com/Cossack9989/e9c1c2d2e69b773ca4251acdd77f2835
gist.github.com

Timeline

Published
Mar 29, 2022
Last Updated
Nov 21, 2024

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