SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2021-42911

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…

CRITICAL 9.8EPSS 3.52%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (3.52%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

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 3.1
9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
3.52% probability · 89th percentile
CISA KEV
Not listed
Weakness
CWE-134
Affected
draytek/vigor2960 firmware · draytek/vigor3900 firmware · draytek/vigor300b firmware
Source
cve@mitre.org

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.