Malicious PDF — malware analysis report

Static analysis result for SHA-256 efbf34a6e2b8324c…

MALICIOUS

PDF

85.3 KB Created: 2021-09-01 00:21:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: f555183f44bba9d41d0185970af620dc SHA-1: 1bef7f1ed459fadfb464a1a395e8f49b27ff48e9 SHA-256: efbf34a6e2b8324c906bb6b3682649a59cb7abffdd33252f3c1077f220a4c155
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate the document functions as a link farm, directing users to multiple external websites, some hosted on potentially compromised or disposable domains. The presence of numerous links and the nature of the heuristics suggest an attempt to distribute malicious content or phish for credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

Heuristics 6

  • 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.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • 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://guijek.com/userfiles/file/tedevujepovimipexusewove.pdf In PDF document text
    • https://istanajp2.com/contents//files/rexolipowewu.pdfIn PDF document text
    • https://mebelpozakazu.ru/wp-content/plugins/super-forms/uploads/php/files/688ed3a3d396aca10ea094c75b4d79c6/fabujuvetexirup.pdfIn PDF document text
    • https://g3az.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b8a08835c7c---19300503003.pdfIn PDF document text
    • https://ctsgroups.asia/images/file/mufebeg.pdfIn PDF document text
    • http://fotobambagiotti.it/userfiles/files/lozegopijit.pdfIn PDF document text
    • https://lolakarimova.uz/ckfinder/userfiles/files/vuvuvamimevomubalev.pdfIn PDF document text
    • http://global-poseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b9777b8d2a5---51008449333.pdfIn PDF document text
    • https://network-italia.it/file/rarugesaledanetepepogov.pdfIn PDF document text
    • http://shyjjc.com/v15/Upload/file/2021814259363974.pdfIn PDF document text
    • https://agilitynd.com/wp-content/plugins/super-forms/uploads/php/files/c830a8818c7da0420c95b620506bc7e8/62660607059.pdfIn PDF document text
    • http://pmdrecycling.com/wp-content/plugins/formcraft/file-upload/server/content/files/16124bffdf369b---93531532358.pdfIn PDF document text
    • https://bulendengin.com/upload/ckfinder/files/58166139950.pdfIn PDF document text
    • http://szentimresiklos.hu/upload/file/54429564469.pdfIn PDF document text
    • http://angelojrobles.com/admin_initial_test/userfiles/file/57630924224.pdfIn PDF document text
    • http://nextgenship.net/upload/file/20210621162424754893.pdfIn PDF document text
    • http://timebank.ru/sites/default/files/photos/pagefile/watuxopemobuv.pdfIn PDF document text
    • http://mas.vacations/wp-content/plugins/formcraft/file-upload/server/content/files/160b5f8f642778---83736655975.pdfIn PDF document text
    • http://scvumaichiramen.com/uploads/files/8439880261.pdfIn PDF document text
    • https://chp-travel.ir/data/file/52042536592.pdfIn PDF document text
    • http://mastrodibaglio.it/userfiles/files/lonesosopononapobabev.pdfIn PDF document text
    • http://riminabda.sk/userfiles/file/revijuliwapij.pdfIn PDF document text
    • http://www.putnamtaxi.net/wp-content/plugins/formcraft/file-upload/server/content/files/160fd1656b9152---kumezezo.pdfIn PDF document text
    • https://aquaprosmart.com/userfiles/files/3320639941.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075cb3298f69---2564148552.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=becoming+book+online+pdfPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In 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_off0000e831.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE831 10720 bytes
SHA-256: 2570bb6a57bc82fe8839efc8a6d39ea44c34b1050192f714f1f185b0eea22a07
font_01_sfnt_off0001004e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1004E 18028 bytes
SHA-256: 46f31536c648b07202265a42def85efb6ccaf651fc1fd5d9fcef40ae7497dcef
font_02_sfnt_off00012ed9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12ED9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1