CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
AI Score
Confidence
High
EPSS
Percentile
87.4%
Grav is a flat-file content management system. Prior to version 1.7.42, the denylist introduced in commit 9d6a2d to prevent dangerous functions from being executed via injection of malicious templates was insufficient and could be easily subverted in multiple ways – (1) using unsafe functions that are not banned, (2) using capitalised callable names, and (3) using fully-qualified names for referencing callables. Consequently, a low privileged attacker with login access to Grav Admin panel and page creation/update permissions is able to inject malicious templates to obtain remote code execution. A patch in version 1.7.42 improves the denylist.
[
{
"vendor": "getgrav",
"product": "grav",
"versions": [
{
"version": "< 1.7.42",
"status": "affected"
}
]
}
]
github.com/getgrav/grav/blob/1.7.40/system/src/Grav/Common/Utils.php#L1952-L2190
github.com/getgrav/grav/commit/71bbed12f950de8335006d7f91112263d8504f1b
github.com/getgrav/grav/security/advisories/GHSA-j3v8-v77f-fvgm
huntr.dev/bounties/3ef640e6-9e25-4ecb-8ec1-64311d63fe66/
www.github.com/getgrav/grav/commit/9d6a2dba09fd4e56f5cdfb9a399caea355bfeb83