CVE-2023-34253
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…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (2.07%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
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.
- CVSS 3.1
- 7.2 HIGHCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 2.07% probability · 80th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-184, CWE-1336, CWE-94
- Affected
- getgrav/grav
- Source
- security-advisories@github.com
References
- https://github.com/getgrav/grav/blob/1.7.40/system/src/Grav/Common/Utils.php#L1952-L2190Issue Tracking
- https://github.com/getgrav/grav/commit/71bbed12f950de8335006d7f91112263d8504f1bPatch
- https://github.com/getgrav/grav/security/advisories/GHSA-j3v8-v77f-fvgmExploit, Vendor Advisory
- https://huntr.dev/bounties/3ef640e6-9e25-4ecb-8ec1-64311d63fe66/Exploit, Third Party Advisory
- https://www.github.com/getgrav/grav/commit/9d6a2dba09fd4e56f5cdfb9a399caea355bfeb83Patch
- https://github.com/getgrav/grav/blob/1.7.40/system/src/Grav/Common/Utils.php#L1952-L2190Issue Tracking
- https://github.com/getgrav/grav/commit/71bbed12f950de8335006d7f91112263d8504f1bPatch
- https://github.com/getgrav/grav/security/advisories/GHSA-j3v8-v77f-fvgmExploit, Vendor Advisory
- https://huntr.dev/bounties/3ef640e6-9e25-4ecb-8ec1-64311d63fe66/Exploit, Third Party Advisory
- https://www.github.com/getgrav/grav/commit/9d6a2dba09fd4e56f5cdfb9a399caea355bfeb83Patch
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.