CVSS2
Attack Vector
LOCAL
Attack Complexity
LOW
Authentication
NONE
Confidentiality Impact
PARTIAL
Integrity Impact
PARTIAL
Availability Impact
PARTIAL
AV:L/AC:L/Au:N/C:P/I:P/A:P
CVSS3
Attack Vector
LOCAL
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS
Percentile
5.1%
In cloudflared
versions < 2020.8.1 (corresponding to 0.0.0-20200820025921-9323844ea773 on pkg.go.dev) on Windows, if an administrator has started cloudflared
and set it to read configuration files from a certain directory, an unprivileged user can exploit a misconfiguration in order to escalate privileges and execute system-level commands. The misconfiguration was due to the way that cloudflared
reads its configuration file. One of the locations that cloudflared
reads from (C:\etc) is not a secure by default directory due to the fact that Windows does not enforce access controls on this directory without further controls applied. A malformed config.yaml file can be written by any user. Upon reading this config, cloudflared
would output an error message to a log file defined in the malformed config. The user-controlled log file location could be set to a specific location that Windows will execute when any user logs in.
CVSS2
Attack Vector
LOCAL
Attack Complexity
LOW
Authentication
NONE
Confidentiality Impact
PARTIAL
Integrity Impact
PARTIAL
Availability Impact
PARTIAL
AV:L/AC:L/Au:N/C:P/I:P/A:P
CVSS3
Attack Vector
LOCAL
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS
Percentile
5.1%