Security Sandbox Bypass with SSTI (Server Side Template Injection) in the Grav CMS
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 1.8.0-beta.27
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
- Exploitation: poc
- Automatable: yes
- Technical impact: total
Summary
Grav is a file-based Web platform. Prior to 1.8.0-beta.27, Grav CMS is vulnerable to a Server-Side Template Injection (SSTI) that allows any authenticated user with editor permissions to execute arbitrary code on the remote server, bypassing the existing security sandbox. Since the security sandbox does not fully protect the Twig object, it is possible to interact with it (e.g., call methods, read/write attributes) through maliciously crafted Twig template directives injected into a web page. This allows an authenticated editor to add arbitrary functions to the Twig attribute system.twig.safe_filters, effectively bypassing the Grav CMS sandbox. This vulnerability is fixed in 1.8.0-beta.27.
Timeline
- CVE published
- CISA SSVC assessment
Exploitation: poc · Automatable: yes · Technical impact: total
- Record last updated
Affected versions
- getgrav grav
fixed in 1.8.0-beta.27
- getgrav/gravPackagist
fixed in 1.8.0-beta.27