Malicious PDF — malware analysis report

Static analysis result for SHA-256 7c1ee9bd669e18f1…

MALICIOUS

PDF

72.0 KB Created: 2021-09-16 11:58:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: cd6116c6010788016c6170877f5b4ba7 SHA-1: 6e2881d79f30c98eebc52b8fdd25ea10a0f3eb0c SHA-256: 7c1ee9bd669e18f18177c0d82e1a10ad1e1235075afad8df263c705c88d6909f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ClamAV as a phishing trojan. It contains numerous external URIs and links to compromised WordPress upload storage, suggesting a phishing or malware distribution lure. The ML classifier also strongly indicated maliciousness. No scripts were extracted, but the PDF structure and embedded links point towards an attempt to redirect the user to malicious content.

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 https://cructi.ru/uplcv?utm_term=cool+math+cookie+clicker PDF link annotation
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/737c6b03ddb6fa527f1f90abff1453b1/32154155911.pdfIn PDF document text
    • http://flemingdecal.com/uploads/assets/file/xezuziv.pdfIn PDF document text
    • http://sieuthibds.net/images/files/59035525381.pdfIn PDF document text
    • https://zenithservicos.com/userfiles/files/26485648212.pdfIn PDF document text
    • http://kruengrangthai.com/files/files/53916913761.pdfIn PDF document text
    • https://gaseg.com/wp-content/plugins/super-forms/uploads/php/files/04hlhlpi02qt7oon4a9ub03bss/21781329503.pdfIn PDF document text
    • https://malabarmail.com/ckfinder/userfiles/files/60778595038.pdfIn PDF document text
    • http://www.casasemio.com.br/ckfinder/userfiles/files/tuxotaxinuwiba.pdfIn PDF document text
    • https://magerp.org/upload/files/86162155600.pdfIn PDF document text
    • http://ateliergermain.org/sites/default/files/file/notogilo.pdfIn PDF document text
    • http://fanghsin.com/uploads/files/202109100017496277.pdfIn PDF document text
    • http://lighthouse-connection.at/myPix/file/zofaragoru.pdfIn PDF document text
    • https://ijp2.com/contents/files/86641237818.pdfIn PDF document text
    • http://medicaldistri.com/ckfinder_files/files/73964854737.pdfIn PDF document text
    • http://farmina.ru/uploads/files/48939737267.pdfIn PDF document text
    • http://vanhacollection.com/images/files/gonaxoginofi.pdfIn PDF document text
    • https://ketex.com/trcgp/ckfinder/userfiles/files/73775055715.pdfIn PDF document text
    • http://vietcem.vn/public/default/ckeditor/files/vawakuba.pdfIn PDF document text
    • http://storemisr.com/uploads/files/9131505179.pdfIn PDF document text
    • http://taiwan-casters.com/userfiles/file/11228776579.pdfIn PDF document text
    • http://adanateknikservis.web.tr/wp-content/plugins/formcraft/file-upload/server/content/files/161372029bb7f2---gazetosodip.pdfIn PDF document text
    • https://thewentworthco.com/wp-content/plugins/super-forms/uploads/php/files/djdcfe9t08788iagavqaje18h8/pudig.pdfIn PDF document text
    • http://orem.mn/uploads/files/midinamam.pdfIn PDF document text
    • https://inchirierielicopter.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613219b34d041---11288103105.pdfIn PDF document text
    • 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_off0000b7c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB7C5 16640 bytes
SHA-256: 59472d8cc3eea8bd9d52ab8b016b566a966d33290f8545d465d1f2bfeb193732
font_01_sfnt_off0000e2a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2A4 10348 bytes
SHA-256: 2ceac4bde0bfc3075ed3c278377af7e6436e15786e9762bbd982f44439e5308f
font_02_sfnt_off0000fa06.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA06 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1