Malicious PDF — malware analysis report

Static analysis result for SHA-256 8766437be61cdec3…

MALICIOUS

PDF

84.8 KB Created: 2021-09-01 02:45:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 144ac86e4aade418283afc3695bef900 SHA-1: 5571b861f0f9aa96973dfb39f70a630c21a2a610 SHA-256: 8766437be61cdec3dc833b5200a3ad6a65b429c2ce2616a4403e5ca7557ae6fc
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains embedded JavaScript and numerous external URIs, many of which point to compromised WordPress sites acting as link farms. The embedded JavaScript and the nature of the links suggest an attempt to redirect users to malicious content or phishing sites, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9574

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • External URI info PDF_URI
    PDF contains an external URL action
  • PDF differential parser failed info PDF_DIFFERENTIAL_PARSE_FAILED
    The cross-check parser (pdfminer.six) failed on this file: PDF differential parser failed: PDFSyntaxError. Static heuristics still ran and any of their findings above are valid; only the differential cross-check signal is missing.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://synerhu.ru/uplcv?utm_term=superstitions+about+doors PDF link annotation
    • https://www.mclarenpress.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608fa9f4a2bff---45028031841.pdfIn PDF document text
    • https://ltgtrends.com/wp-content/plugins/super-forms/uploads/php/files/37b58b018148517418dd1c9b7846b2dd/38371935157.pdfIn PDF document text
    • https://pbchistoryonline.org/uploads/file/latilagosizapeg.pdfIn PDF document text
    • http://musicpark-live.de/userfiles/file/95257265775.pdfIn PDF document text
    • http://udemadriatic.com/userfiles/files/88036589504.pdfIn PDF document text
    • http://kurier48.pl/files/userfiles/file/loporuzu.pdfIn PDF document text
    • http://solamsys.com/userData/board/file/40438592886.pdfIn PDF document text
    • https://alakharia.com/public_html/userfiles/file/rowumo.pdfIn PDF document text
    • http://murasakijr.com/uploads/files/89572471526.pdfIn PDF document text
    • https://adiwirawanbali.com/wp-content/plugins/super-forms/uploads/php/files/341c9bfdfb835413badd30387850fede/54572858697.pdfIn PDF document text
    • http://freemansphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608226f5314ba---wulekazexapopukexaro.pdfIn PDF document text
    • http://aeskulap24h.com/wp-content/plugins/formcraft/file-upload/server/content/files/160808529a367e---44574447471.pdfIn PDF document text
    • https://micast.de/wp-content/plugins/super-forms/uploads/php/files/7bunot2nb9qk56rt509kq6givp/85383804690.pdfIn PDF document text
    • http://docando.es/js/ckfinder/userfiles/files/89721290439.pdfIn PDF document text
    • http://okwmd.com/upload/fckeditor/file/22018009875.pdfIn PDF document text
    • https://seroinstitute.com/wp-content/plugins/super-forms/uploads/php/files/f010d92aff16e316d2acfa51cdb4531b/katuwujatinoxibema.pdfIn PDF document text
    • https://literie-depot.fr/UserFiles/file/wubap.pdfIn PDF document text
    • http://www.stratcareerservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4a02061f13---budegoxitufedunituxi.pdfIn PDF document text
    • http://treeoflifetolfu.com/clients/0/07/07f122ebb3396bb3f917f2e62af81596/File/zasopatupaxajaxelovurat.pdfIn PDF document text
    • https://ruxthai.com/ckfinder/userfiles/files/dajakegob.pdfIn PDF document text
    • http://nessium.net/userfiles/file/wuwexugupagad.pdfIn PDF document text
    • http://parfumerieindex.nl/images/uploads/1572732521.pdfIn PDF document text
    • https://facades-metal.ch/ckfinder/userfiles/files/1146502335.pdfIn PDF document text
    • http://www.meglobalinc.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16083c15add998---3920365253.pdfIn PDF document text
    • https://provisionsinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d404c63752---56238565272.pdfIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f398.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF398 18524 bytes
SHA-256: d78d0c86eb5eb6b242339cdc25db9a881da6b20ba7be82fe31872b17028ad5f7
font_01_sfnt_off0001228d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1228D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013aa4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13AA4 10652 bytes
SHA-256: 26150afdc290434f21e567a516768a8959ae97ad7dfed0198deaa05bd658a2ed