Malicious PDF — malware analysis report

Static analysis result for SHA-256 83b5a8826241788f…

MALICIOUS

PDF

83.4 KB Created: 2021-08-16 15:26:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 44e80f9cb1e38eaf7ef92bc1b75a0ed0 SHA-1: a56508b213666ae2b9efa74417c8fd63aa542ab2 SHA-256: 83b5a8826241788f683c35bb56fc1c53b349d26f0a64309a1ebd0971644fb2fd
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as Pdf.Phishing.Trojan. The numerous embedded URLs and link farm indicators suggest the primary purpose is to redirect users to compromised websites or phishing pages. No scripts were extracted, but the presence of external links and the overall structure point towards a social engineering attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://pixomot.ru/uplcv?utm_term=what+are+the+benefits+of+non-probability+sampling PDF link annotation
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/r8f8krbgui742276hue6tdpeq6/kogotodow.pdfIn PDF document text
    • http://esoftland.com/userfiles/file/jebotunije.pdfIn PDF document text
    • http://gaongonmaiphuong.vn/webroot/img/files/33785874014.pdfIn PDF document text
    • http://zpb-maciejewski.pl/upload/fck/file/pujewifazisojasalinajiren.pdfIn PDF document text
    • https://duhocblueocean.vn/ckfinder/userfiles/files/40428164897.pdfIn PDF document text
    • http://cargo3030.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1606c9bf9f0343---35928968422.pdfIn PDF document text
    • http://automsystem.com/UploadFile/file/20210807205540277.pdfIn PDF document text
    • https://argumentua.com/i/file/pirarurazeje.pdfIn PDF document text
    • http://www.inhd.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c329178af01---lodigixafudirepad.pdfIn PDF document text
    • http://moonlightmontessori.com/upload/files/60827680888.pdfIn PDF document text
    • http://malir-naterac.info/UserFiles/File/68168611043.pdfIn PDF document text
    • https://www.avantagesapp.com/uploads/files/48483280618.pdfIn PDF document text
    • http://www.finanzanlagen-honorarberatung.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609da3ae20713---lixajek.pdfIn PDF document text
    • http://wacommerce.net/home/integrity/public_html/ckfinder/userfiles/files/59537441624.pdfIn PDF document text
    • http://shqinze.net/admin/upimg/file///nadavuv.pdfIn PDF document text
    • https://benjamindreyer.com/wp-content/plugins/super-forms/uploads/php/files/1ebcacae6307fe6e46a43f4c819b6bd4/90533674322.pdfIn PDF document text
    • https://ecoinkworld.com/wp-content/plugins/super-forms/uploads/php/files/a3e46bb243f8ecff5eea54b0a7cd8bd9/80080728888.pdfIn PDF document text
    • https://imagebeaute.fr/userfiles/file/59555520826.pdfIn PDF document text
    • https://directprocessors.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076136160ed9---41324545498.pdfIn PDF document text
    • https://sportyou.fr/ckfinder/userfiles/files/97163141757.pdfIn PDF document text
    • https://educationindiajournal.org/ckfinder/userfiles/files/66841554927.pdfIn PDF document text
    • https://kogan-photo.ru/wp-content/plugins/super-forms/uploads/php/files/a5211f078add2679c42b3c65d18b2577/43564332507.pdfIn PDF document text
    • http://erdivigado.hu/userkepek/file/44230123526.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_off0000e010.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE010 17260 bytes
SHA-256: 618b521dfb16e04da2efe83bf6366cb54bad08405d9dc597b4fe2b69cb38538a
font_01_sfnt_off00010d10.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D10 11088 bytes
SHA-256: f068733f6fab012cec5e77c8804467239e67e5491fc1e8e2ad66805af665fd93
font_02_sfnt_off00012694.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12694 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1