Malicious PDF — malware analysis report

Static analysis result for SHA-256 44110b751b1f9c11…

MALICIOUS

PDF

70.3 KB Created: 2021-09-28 04:04:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-22
MD5: 42242a52a6f98aeaa021cdf14e67e901 SHA-1: 0632731e7f464f00d15cd2c8a48f8d5f5a0d0782 SHA-256: 44110b751b1f9c11e800a69272322a07ba44bb34ff72f3ab7235ec2614d38793
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as 'Pdf.Phishing.Trojan' and an ML classifier indicated a high probability of maliciousness. The document contains a link farm with numerous URLs pointing to PDF files hosted on compromised websites, suggesting a phishing or SEO poisoning campaign. No scripts were extracted, and the document body was unreadable binary data.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 http://www.studiolegalefusimorelli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1615239d57e459---70964020511.pdf In PDF document text
    • http://sitoad.com/bbqjoekey/files/202109020122526947.pdfIn PDF document text
    • http://www.grifin.sk/files/pafuxonotot.pdfIn PDF document text
    • http://e-store-sys.com/userfiles/file/4467320950.pdfIn PDF document text
    • http://euroambulans.pl/userfiles/file/gazodoj.pdfIn PDF document text
    • https://hatinhjobs.com/upload/files/vosubufifaseja.pdfIn PDF document text
    • https://www.drserapkagan.com/wp-content/plugins/super-forms/uploads/php/files/8mggqh8gv61qhfnaqn2vnergf9/bipalotitamerade.pdfIn PDF document text
    • http://whitedwarf.ru/public/images/ckfinder/files/59974516327.pdfIn PDF document text
    • http://soft-pro.hr/upload/datoteke/97869512438.pdfIn PDF document text
    • https://www.unicodesystems.com/wp-content/plugins/super-forms/uploads/php/files/nsac6o5rmejasn3fhu3fp3uba0/40717715128.pdfIn PDF document text
    • http://arohitourandtravels.com/userfiles/file/gumogutuvidum.pdfIn PDF document text
    • http://www.gobarging.com/uploads/textareas/file/xoxuretizusigalatixevede.pdfIn PDF document text
    • http://tecniagua.es/uploads/ckfinder/files/69836195006.pdfIn PDF document text
    • http://td-mg.ru/uploads/files/fokutibolidakiwenuxilepe.pdfIn PDF document text
    • http://emilygrilltogo.com/uploads/files/wakodeweje.pdfIn PDF document text
    • http://apnm.indexint.net/ckfinder/userfiles/files/makalurezufipal.pdfIn PDF document text
    • https://goodline.by/userfiles/file/rosakupafekewedanadixofa.pdfIn PDF document text
    • https://drivingschoolofnorthtexas.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141693b74a87---47456005513.pdfIn PDF document text
    • http://www.zywawiara.pl/pliki/zekuripokafusu.pdfIn PDF document text
    • http://dallapietamarchisio.it/userfiles/files/4410745946.pdfIn PDF document text
    • http://aumnat2car.com/ckfinder/core/connector/php/upload/files/21552151923.pdfIn PDF document text
    • http://karaokejdi.com/ckfinder/core/connector/php/upload/files/ponefa.pdfIn PDF document text
    • http://nanopena.cz/upload/file/47185150137.pdfIn PDF document text
    • http://mwbright.com/upload_fck/file/2021-9-1/20210901213111559142.pdfIn PDF document text
    • https://callhfelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/16150c6bacce14---buwoxinavir.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=super+mario+bros+wii+u+isoPDF 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_off0000b401.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB401 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cc18.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC18 10568 bytes
SHA-256: 46a090d1dd7b18496676a91babac377e9f8ba846807dbe2eaf336c474e95fff0
font_02_sfnt_off0000e402.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE402 15484 bytes
SHA-256: b237287141c572f46f8daa96cd9f366f77add1ceeedb597a9aa5c33052f22894