Malicious PDF — malware analysis report

Static analysis result for SHA-256 66ff59883cd89d79…

MALICIOUS

PDF

93.8 KB Created: 2021-06-19 22:10:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: c6c5b7e92cd9deb776f96bc8246aaffd SHA-1: d104ccdaf6c87b19e377b809dd392b619f2a4910 SHA-256: 66ff59883cd89d793e111f310530388193d72cab739be6da6bd6826672d7beda
156 Risk Score

Malware Insights

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

The file is identified as malicious by ML classifiers and ClamAV, with multiple heuristics indicating it is a link farm hosted on compromised CMS uploads. The document body, though heavily obfuscated, suggests a 'Servqual questionnaire sample' lure. The embedded URLs point to various compromised WordPress sites, likely serving as a distribution point for further malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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 http://www.naturapreserved.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609471f2b2c5d---lagina.pdf In PDF document text
    • http://www.argentum.com/wp-content/plugins/super-forms/uploads/php/files/2h96k9s56e192svm0tm0qv3h2m/dusemotofarotiribopekawi.pdfIn PDF document text
    • https://wills.sg/wp-content/plugins/super-forms/uploads/php/files/67f225163ff4bb2fdda6e14c1ff62c96/76361088419.pdfIn PDF document text
    • https://alutat.com/data/file/14020999209.pdfIn PDF document text
    • https://tortugafilms.ca/adminfiles/file/rurikunilopixa.pdfIn PDF document text
    • http://fogathajtohirek.hu/fckfiles/file/lefililubululanirixiru.pdfIn PDF document text
    • https://adikkeempat.com/contents//files/78240958263.pdfIn PDF document text
    • https://webmodels.studio/wp-content/plugins/formcraft/file-upload/server/content/files/1606d0f6d2e922---36661835252.pdfIn PDF document text
    • http://luxe-pools.fr/i/File/31910506696.pdfIn PDF document text
    • https://soba05.org/wp-content/plugins/super-forms/uploads/php/files/d8ccf16f7d2d0cb2bd714525dc7af193/84279931839.pdfIn PDF document text
    • http://msamerica.net/clients/873634/File/29249144307.pdfIn PDF document text
    • http://connect-senior.ch/uploades/userfiles/file/fegomokaweri.pdfIn PDF document text
    • http://crisismobile.com/ckfinder/userfiles/files/84458542194.pdfIn PDF document text
    • https://www.ediliziaindustriale.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609549413f833---85723231477.pdfIn PDF document text
    • https://studio45.live/wp-content/plugins/super-forms/uploads/php/files/8fmp3nbhp8sdbtm2diot606qkd/kemavoketovofupilixeza.pdfIn PDF document text
    • https://kogan-photo.ru/wp-content/plugins/super-forms/uploads/php/files/988d7e5889c81b06dd9c1596c78620ac/vibiv.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=servqual+questionnaire+samplePDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00013082.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13082 5256 bytes
SHA-256: aa09cd52b70e84c01dc9ce734b5a69315f0f219c3bb16dd974b202f73eb4b7eb
font_01_sfnt_off00014253.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14253 12372 bytes
SHA-256: bdcf0f68d2db477fc34950aafa5f35de5066a71a1dd8209b4a6c70c03068d06a